Location Of Perforation Research Articles

Experimental investigation using demountable steel-concrete composite reduced web section (RWS) connections under cyclic loads

This paper presents an experimental study of demountable steel-concrete composite reduced web section (RWS) connections for use in seismic areas. Four composite connection specimens were subjected to sagging and hogging moments to investigate the performance of RWS connections under reversible actions. For such purpose, a single web opening was created near the beam-column joint. Focus was made on the effects of perforation location and composite beam-slab action induced by bolted shear studs within the protected zone. Results indicate that employing RWS connections for seismic retrofit is a viable solution capable of achieving a performance similar to that observed for RBS connections in new buildings. Notably, a Vierendeel Mechanism is formed, allowing for plasticity development in the beam. All RWS connections were capable of achieving an interstory drift larger than 4%, thereby complying with the performance targets set by ANSI/AISC 358-16, ANSI/AISC 341-16 and EC8. Moreover, the deformation of beam-slab shear-transfer bolts was small enough to allow for disassembly after the tests, indicating that the proposed solution could enable reuse and post-earthquake retrofitting.

DALK combined intralamellar tectonic patch graft: an alternative approach to treat frank corneal perforation

BackgroundDeep anterior lamellar keratoplasty (DALK) has gained popularity in cases of corneal thinning and leaking descemetocele. In this study, we introduced an intralamellar tectonic patch graft in addition to conventional DALK procedures to treat frank cornea perforation.MethodsThis retrospective case series included 13 patients (13 eyes) with frank corneal perforations who underwent DALK combined with intralamellar tectonic patch graft between December 2015 and December 2021. In addition to the standard DALK procedure, the perforation site was repaired with an extra intralamellar tectonic patch graft. The collected data included patient demographics, aetiology, size and location of the corneal perforation, visual acuity, surgical details, and postoperative complications.ResultsSeven patients underwent autologous intralamellar patch grafts, whereas six received allogeneic ones. Anatomical success was achieved in all patients. The mean postoperative follow-up was 33.31 ± 25.96 months (6–73 months). The postoperative visual acuity (0.90 ± 0.65 logMAR) was significantly improved (P = 0.003) compared to the preoperative score (1.74 ± 0.83 logMAR). Best corrected visual acuity (BCVA) improved in 12 eyes (92.3%). The mean endothelial cell density was 2028 ± 463 cells/mm2, 6–12 months postoperatively. There was no recurrence of perforation, and the anterior lamellar graft remained transparent in 12 patients (92.3%). Postoperative complications included epithelial defects (23.1%), ocular hypertension (15.4%), and cataract (7.7%).ConclusionsDALK combined with intralamellar tectonic patch graft may serve as a secure and effective alternative in treating frank corneal perforation, with reduced complications compared to conventional penetrating keratoplasty.

Multi-Objective Optimization of Air-Cooled Perforated Micro-Pin Fin Heat Sink Via an Artificial Neural Network Surrogate Model Coupled With NSGA-II

Abstract This research aims to create an artificial neural network (ANN) regression model for predicting the performance parameters of the perforated micro-pin fin (MPF) heat sinks for various geometric parameters and inflow conditions. A three-dimensional computational fluid dynamics (CFD) simulation system is developed to generate dataset samples under different operational conditions, which are specified using Latin hypercube sampling (LHS). An ANN model is first obtained by optimizing the model hyper-parameters, which are then deployed to learn from the input feature space that consists of perforation diameter, perforation location, and inflow velocity. For accurate training of the ANN, the model is trained over a range of uniformly distributed data points in the input feature space. The developed multi-layer model predicted Nusselt number and friction factor with the mean absolute percentage error of 4.45% and 1.80%, respectively. Subsequently, the developed surrogate model is used in the optimization study to demonstrate the application of the surrogate model. A multi-objective non-dominated sorting genetic algorithm (NSGA-II) is used to perform the optimization of the perforation location, diameter, and inflow conditions. Negative of the Nusselt number and friction factor are chosen as objectives to minimize. A Pareto front is obtained from the optimization study that shows a set of optimal solutions. Thermal performance of the perforated MPF is increased between 11.5% and 39.77%. The optimizer selected a significantly smaller hole diameter at a higher location and a faster speed to maximize the Nusselt number and minimize the friction factor.

Distal profunda femoris artery perforator island flap for distal thigh and knee reconstruction: a CT-based anatomical analysis and a case-series study.

Locoregional flap options for reconstructing defects of the anterolateral distal thigh/knee region are limited. The distal profunda artery perforator island (PAPI) flap is a local fasciocutaneous propeller-type flap that utilizes the most distal perforator of the profunda femoris artery. The aim of this study is to conduct a CT-based angiographic analysis of the perforator system of the profunda femoris artery and present outcomes on the application of the PAPI flap in the management of post-oncologic defects of the distal thigh and knee. CT angiograms were utilized on the lower limbs of 25 healthy patients (mean age, 57 years; 76% male) and the number and location of septocutaneous perforators with a diameter greater than 1 mm were measured. A case series of patients undergoing reconstruction of post-ablative defects which involved the anterolateral and posterior knee performed by the senior author were reviewed. CT angiography demonstrated a robust collection (mean 3.5, range 2 to 5) of septocutaneous perforators from the profunda femoris artery with the most distal perforator located 3.3 cm from the superior patella border. The PAPI flap was successfully used in 10 patients (6F; 4M; mean age 60.6 years; range 30 to 88 years) with a mean defect size of 87.5 cm2 (range 48 to 150 cm2 ). Hand-held Doppler was used to detect the perforator. No flap loss was encountered, and no knee function limitation was noted at follow-up. Minor complications include seroma (1) and intra-articular infection (2). We conclude that the distal PAPI flap is a reliable and versatile flap that has potentially wide applications.

A time-bounded approach for reducing runtime of well placement optimization using PSO and PSOGA algorithms

Determining the optimal drilling locations and well production/injection rates is a highly complex decision in reservoir development. The present study aims to optimize well placement and production/injection rates through the application of intelligent search algorithms. The Particle Swarm Optimization (PSO) and combined Particle Swarm Optimization-Genetic Algorithm (PSOGA) have been chosen as the optimal means to achieve this objective. The Net Present Value (NPV) of the project serves as the objective function, with decision variables including the location of wells, perforation, and flow rates. To evaluate the performance of the algorithms in optimizing well placement and flow rates, a heterogeneous reservoir model has been used. In order to reduce optimization runtime, a novel method has been presented. This method involves changing the termination condition, such that the entire optimization time is considered rather than the maximum iterations. The population size can be added to enhance algorithm convergence. Thus, modified algorithms, namely TPSO and TPSO-GA, have been introduced. The results of determining the termination condition on the TPSO-GA algorithm are quite promising. By setting a 24-h termination condition or a 70% reduction in the basic runtime, and with a population size of 30 agents, the same values of the objective function can be obtained. Furthermore, the impact of two parameters within the objective function, namely the oil price and discount rate, has also been explored.

Surgical management for the perforation of digestive tract with intraabdominal infection

Perforation of digestive tract with intra-abdominal infection is one of the common causes of emergency surgery. After the resection with intestine, primary anastomosis or stoma remains a subject of debate. With the continuous improvement of surgical technology and the need to improve patients' quality of life, primary anastomosis is supposed to be the most ideal surgery. However, the rate of stoma is still high due to concerns about postoperative anastomotic leakage. This paper summarizes the surgical treatment of intra-abdominal infection caused by gastrointestinal perforation in recent years, and discuss the best operation plan according to the perforation location and etiology. We also discuss a variety of treatment methods for the prevention of anastomotic leakage (perioperative management, gastrointestinal anastomosis, enteric lavage decompression and other techniques) to improve the primary anastomosis, improve the quality of life of patients and reduce the medical burden.

Preoperative planning using virtual reality and computed tomography angiogram in deep inferior epigastric perforator flap breast reconstruction

The gold standard for preoperative planning of deep inferior epigastric perforator (DIEP) flap breast reconstruction uses computed tomography angiography (CTA). Virtual reality (VR) circumnavigates the limitations of CTA by reconstructing a fully immersive and interactive 3D representation of the scan. Scans of 44 patients who underwent DIEP flap breast reconstruction were retrospectively reviewed and compared using CTA and VR imaging modalities. The objective of this research was to compare perforators found using VR to the ones identified using conventional CTA. A correlation was found between the imaging modalities for unilateral (R = 0.96 (CI = 0.92, 0.98)) and bilateral (R = 0.93, (CI = 0.83, 0.97)) DIEP flap surgeries when comparing perforator location related to the umbilicus. Multivariable ordinal logistic regression found that higher intramuscular course length (IMC) is associated with the number of perforators found per side (OR = 1.79 (CI = 1.24, 2.6)), and medial location (OR = 2.85 (CI = 1.38, 5.87)). Larger vessel caliber (VC) is associated with shorter IMC (T2 vs. T3, OR = 3.34 (CI = 1.49, 7.49)), and branching in adipose tissue (AB) is associated with higher VC (T1 vs. T3, OR = 0.02 (CI = 0.007, 0.08); T2 vs. T3, OR = 0.24 (CI = 0.11, 0.55)). Overall, preoperative planning using VR was easy to use, safe, more intuitive, and provided in a time-efficient manner, more information about perforant characteristics. VR can improve the surgeon’s decision accuracy, relating to the best perforators for harvesting, in a shorter time period.

Criteria for discriminating layer-penetration fracturing considering pressure drop and interfaces

Accurately predicting fracture height growth in a stratified reservoir presents a significant challenge. In this study, we have developed a semi-analytical prediction model for fracture height growth that accounts for pressure drop effects and considers the influence of bedding interfaces, all based on the principles of equilibrium height theory. The methodology involves solving intricate nonlinear equations and generating fracture height profiles, systematically investigating the effects of various factors: in-situ stress, fracture toughness, fluid density, and perforation location on fracture height. Sensitivity analysis of the model has revealed findings: (1) The presence of a stress barrier leads to a substantial increase in the induced stress required for fracture height growth. In particular, the stress barrier inhibits growth on one side while promoting it on the opposite side. (2) The influence of the fracture toughness barrier on fracture height growth, while significant, is overshadowed by that of the stress barrier. An increase in the fracture toughness of the rock decelerates the rate of fracture height growth but simultaneously raises the required induced stress for layer penetration. (3) Increasing the density of the fracturing fluid exerts a dual effect, slowing the growth rate of the upper fracture tip while accelerating the advancement of the lower fracture tip. Higher fluid density, under constant perforating pressure, results in a noticeable reduction in overall fracture height. (4) Fracture growth from the low-stress layer to the high-stress layer required an increase in induced stress. The research findings not only provide essential data on fracture height profiles, enhancing the applicability of the pseudo-3D hydraulic fracture propagation model, but also contribute to the refinement of governing equations within hydraulic fracture modeling.

Accuracy analysis of traditional acupoint location and the coincidence of cutaneous arterial perforators and acupoints.

Several reports have shown a coincidence relationship between perforators and acupoints. However, there have been few previous reports of objective experimental methods to verify the reliability of the accuracy of acupoint location (APL) with nearby perforators. This research aimed to determine the internal agreement of the APL of five acupuncturists and to analyze the coincidence rate of acupoints with nearby perforators. Three two healthy volunteers were recruited with the inclusion and exclusion criteria. Three TCM clinical physicians determined acupoints in areas of the lower limb of participants. Two microsurgeons sketched corresponding regions based on the most common skin flap operation sites, located bone markers, and drew the skin flap axis. Doppler ultrasound was used to mark the perforator point and the distances measured for both points. There is no significant difference in the distance between the acupoints and perforators localization in different groups, and there are significant differences between the angle formed by acupoints and penetrators in all groups. All the points located by the traditional Chinese medicine (TCM) therapists are distributed around the dot. The distance between the coordinate point (A-B) of Wēnliū (LI7) localization is the largest, reaching 16.6 mm. The accuracy of the acupoint location of each physician is limited by the clinical experience of physicians, and the difference among them is significant. There is a certain correspondence between the location of acupoints and perforators, which needs further studies to confirm.

Outcomes of N-butyl-2-Cyanoacrylate Tissue Adhesive Application in Corneal Perforation Disorders: Consecutive Case Series.

The purpose of this study was to report the success and long-term outcomes of cyanoacrylate tissue adhesive (CTA) application in the management of corneal perforation disorders. This retrospective case series describes the profile and outcomes of eyes that underwent CTA for corneal perforation over an 11-year period from January 2009 until January 2020 at a tertiary eye centre in the United Kingdom. In total, 25 eyes underwent CTA application during the study period. Non-traumatic sterile corneal melt was responsible in more than half of the cases (56.0%; n = 14) followed by infection (32.0%; n = 8) and trauma (12.0%; n = 3). Median size of perforation was 2.0mm (interquartile range, IQR 1.0-3.0). The most common anatomical location of corneal perforation was central (56.0%; n = 14). Ocular surface disease was seen in almost all eyes except two (92.0%; n = 23) with dry eye disease being the most common (48.0%; n = 12). Amongst 23 eyes that completed follow-up (median 27months; IQR 9.5-46.5), single CTA application was successful in achieving intact globe in 13 (56.5%) eyes and repeat gluing sealed total of 20 (86.9%) eyes. Survival analysis showed cumulative success of 71.0% and 51.2% at 90 and 250days, respectively. The CTA was retained in the eyes for median of 94.0days (IQR 30.0-140.5). A total of five patients developed adverse events, including endophthalmitis (n = 2), following CTA application. CTA was highly effective in sealing corneal perforations in acute setting and showed moderate long-term success. However, multiple applications are often required.

Application of modified articular disc anchorage in treating the perforation and rupture of temporomandibular joint disc.

This study aimed to use modified articular disc anchorage in treating old irreducible temporomandibular joint (TMJ) disc displacement with perforation and rupture, as well as to explore its efficacy. A total of 31 patients (34 sides) with 47 TMJ disc perforations who underwent surgical treatment in the Affiliated Stomatolo-gical Hospital of Nanchang University from January 2018 to December 2021 were selected. According to the location of disc perforation, it has five types: posterior disc perforation (typeⅠ), anterior disc perforation (typeⅡ), lateral disc perforation (type Ⅲ), composite disc perforation, and destruction disc perforation. The modified methods of disc anchoring were divided into two types according to the location of the perforation. TypesⅠandⅢ disc perforation were trea-ted by posterior anchoring method. For posterior ancho-ring, a screw was implanted into the posterolateral side of the condylar neck, and the disc was fixed on the screw by horizontal mattress suture. TypeⅡdisc perforation and compo-site disc perforation combined typeⅡperforation were treated by anterior and posterior double-anchoring method. For anterior anchoring, anchor screws or holes were placed at the anterior edge of the condylar neck, and horizontal mattress suture was performed at the posterior edge of the anterior perforation with an anchor wire. The articular disc was then fixed on the anchor screws or holes. For the posterior anchoring method, it was the same as the previous one. Paired t test was used to analyze the visual analog scale (VAS), maximum interincisal opening (MIO), and TMJ disorder index (CMI) of the patient before surgery and 1, 3, and 6 months after surgery. Disk-condyle position relationship by magnetic resonance imaging and postoperative quality of life in postoperative were analyzed. The incidence of perforation was 41.2% (14/34) in typeⅠ, 11.8% (4/34) in typeⅡ, 8.8% (3/34) in typeⅢ, 29.4% (10/34) in composite type, and 8.8% (3/34) in destruction type. The VAS, MIO, and CMI at 3, 6 months after operation significantly improved compared with those before operation (P<0.05). The effective reduction rate of disc was 96.77% (30/31). The quality of life at 6 months after surgery was 47.22±2.13, and the rate of excellent evaluation was 96.4% (27/28). Modified articular disc anchorage achieves a good curative effect for treating temporomandibular joint disc perforation and rupture. Nevertheless, its long-term effect requires further observation.

A Simplified Algorithmic Approach to Vulvar Reconstruction According to Various Types of Vulvar Defects.

Various surgeons adopt various vulvar reconstruction methods for different types of vulvar defects to restore anatomical structures. Vulvar reconstruction has relatively few references as it is performed in many different ways. Our report aimed to create a simplified reconstruction algorithm that can be used to select the reconstruction flap and to compare clinical outcomes. The patients who underwent vulvar reconstruction between April 2017 and May 2020 were retrospectively reviewed. The reconstruction flap was selected according to a suggested algorithm, which accounted for the defect location depending on the vulvo-thigh junctional crease-the visual landmark of the inferior pubic ramus-and proper perforator location. Postoperative surgical complications, functional outcomes, and oncologic outcomes were analyzed according to the histologic and flap types. Forty-seven patients underwent reconstruction with 31 internal pudendal artery perforator flaps (66%) and 16 profunda artery perforator flaps or transverse upper gracilis flaps (34%). The histologic type included 21 extramammary Paget disease (44.7%), 20 squamous cell carcinoma (42.6%), and 6 other types (12.8%). Postoperative complications, including wound and functional complications, occurred in 10 patients (21.3%). There were more cases of wound complications with profunda artery perforator flaps and transverse upper gracilis flaps (37.5%) than those with internal pudendal artery perforator flaps (12.9%) (P = 0.04). There were 7 cases (14.9%) of 2-year oncologic recurrence with no significant differences in terms of histologic or flap types. According to our suggested simplified algorithm, various types of flaps resulted in reliable surgical outcomes with minimal complication rates and acceptable functional and oncologic outcomes, and the primary goals of vulvar reconstruction were achieved effectively. Using our algorithm, selection of the reconstruction method could be simplified and specified despite the complexity of vulvar defects.

Prestrain in the eardrum investigated using laser-ablation perforation: A proof of principle study on the New Zealand white rabbit

While the presence of residual stress (also called prestress) in the tympanic membrane (TM) was hypothesized more than 150 years ago by von Helmholtz (1869), little experimental data exists to date. In this paper, a novel approach to study residual stress is presented. Using a pulsed laser, the New Zealand white rabbit TM is perforated at seven predefined locations. The subsequent retraction of the membrane around the holes is computed using digital image correlation (DIC). The amount of retraction is the so-called prestrain, which is caused by the release of prestress due to the perforation. By measuring the prestrain using DIC, we show that residual stress is clearly present over the entire rabbit TM surface. In total, fourteen TMs have been measured in this work. An automated approach allows tracking the holes’ deformation during the measurement process and enables a more robust analysis than was previously possible. We find similar strains (around 5%) as reported in previous work, in which slits were created manually using flattened surgical needles. However, the new approach greatly reduces measurement time, which minimizes dehydration artifacts. To investigate the effect of perforation location on the TM, the spatial decrease of the prestrain (α) around the perforation was quantified. Perforations inferior to the umbo showed the least negative α values, i.e., the most gradual decrease around the hole, and were the most consistent. Perforations on other locations showed more negative α values, i.e., steeper decrease in strain, but were less consistent across samples. We also investigated the effect of the holes’ creation sequence but did not observe a significant change in the results. Overall, the presented method allows for consistent residual stress measurements over the TM surface. The findings contribute to our fundamental knowledge of the mechanics of the rabbit TM and provide a basis for future work on human TMs.

Reconstruction of Hand Dorsum Defect Using Double Perforators-Based Anterior Interosseous Artery Island Flap: A Case Report and Description of a New Anterior Interosseous Artery Perforator.

The anterior interosseous artery (AIA) perforator flap is not commonly used in hand dorsum reconstruction compared with alternatives. However, it is a versatile flap with several advantages. Literature on the AIA perforator flap is based on the dorsal septocutaneous branch (DSB), which branches from the AIA and passes through fascia between the extensor pollicis longus (EPL) and extensor pollicis brevis muscles. In the described case, the authors reconstructed a hand dorsum defect in a 78-year-old man using an AIA perforator flap with double perforators supplied by the DSB and a new perforator branching from the distal than DSB. No complication was encountered, and the flap survived completely. A retrospective computed tomography review revealed the presence of the new perforator in 14 of 21 patients. Two types of new perforator were observed. One passed through the ulnar side of the extensor indicis proprius (EIP) muscle and penetrated fascia between the extensor digitorum minimi and extensor digitorum communis tendons, whereas the other passed between the EPL and EIP muscles. This report describes the anatomical location and clinical application of the new AIA perforators. The double perforators-based AIA flap provides a straightforward, reliable means of reconstructing hand dorsum defects.

Perforators Detected in Computed Tomography Angiography for Anterolateral Thigh Free Flap: Am I the Only One Who Feels Inaccurate?

The number, location, and pattern of perforators in anterolateral thigh(ALT) flap vary and predicting them preoperatively will aid in reconstructing complex head and neck defects. This article suggests guidelines for utilizing CTA imagery to predict perforators of ALT-free flaps. We retrospectively analyzed 53 Korean patients who underwent reconstruction with ALT flap in our department from March 2021 to July 2022. The location, course, origin, and pedicle lengths predicted in CTA and confirmed in the operation field were recorded and compared. Among the 85 intraoperatively-found perforators, 79 were also identified in CTA. Six perforators unidentified in CTA were newly found intraoperatively. The positive predictive value of CTA for the perforator was 100%, with a sensitivity of 79/85 = 92.9%. Of the 79 perforators depicted by the CTA for the flap, CTA and intraoperative findings for the course were consistent in 52 cases, a 9.6 mm median discrepancy being noted between the actual location and CTA. The overall pattern or location of perforation was not significantly different between the two, although some differences were observed. It is suggested that the addition of Doppler imaging, in conjunction with CTA, can aid in perforator detection and help minimize such discrepancies.

An Insight Into the Effect of Odontogenic Keratocysts on Surrounding Structures: Cone-Beam Computed Tomography-Based Analysis of Cases.

Introduction An odontogenic keratocyst (OKC) is a benign intraosseous lesion with potential to demonstrate aggressive and invasive behavior. The aim of this retrospective study was to analyze the imaging features of the OKCusing cone-beam computed tomography (CBCT) and to evaluate the association between the internal structure of the lesion and the effect of the lesion on surrounding structures. Methods Overall, 32 CBCT scans of histopathologically diagnosed cases of OKC were analyzed retrospectively. The following variables were analyzed: anatomic location of the lesions (mandible body (right/left), ramus (right/left), mandible body+ramus (right/left), maxilla (right/left), and both jaws), the internal structure of the lesion (unilocular/multilocular), and the effect ofthe lesion on the surrounding anatomical structures (involvement of the inferior alveolar nerve canal (IANC), displacement of the IANC, cortical expansion, displacement of the tooth, resorption of the root, associated impacted tooth, associated missing tooth). We also looked for the association between the internal structure and the effect of the lesion on anatomic structures. Results Out of 32 cases, 29 (90.6%) cases involved the mandible alone. Statistically significant association (p-value 0.005) was present between the internal structure and mean age of presentation as well as between the internal structure and impacted tooth (p-value 0.027). The association between the internal structure and other variables was statistically not significant. Conclusions The radiographic features of OKCs can be variable, and these lesions have a considerable effect on the tooth, IANC, and cortical bone. Significant association was found between the internal structure, age, and impacted tooth. Since OKCs have a high recurrence rate, CBCT is advised for evaluating the extent and location of any cortical perforations.

Unconventional surgery for thoracic esophageal rupture with empyema and mediastinitis: a case report and literature review

Treatment of esophageal perforation or rupture is complicated and controversial, especially in advanced cases. In fact, it is generally accepted that this disease must be treated individually according to the location, causes and clinical features of rupture or perforation. A very rare case was admitted to our department, who was injured 5 days ago by high-pressure gas of a running air compressor and resulted in a long-term longitudinal rupture of the thoracic esophagus. Although the patient suffered from empyema and mediastinitis at the same time, and his condition was very serious, the debridement and desquamation of empyema were still implemented, followed by left thoracic esophagectomy and left neck approach esophagogastrostomy in the same period successfully. The patient got a good result finally.

Application of abdominal ultrasonography in surgical necrotizing enterocolitis: a retrospective study.

Necrotizing enterocolitis (NEC) is a severe inflammatory bowel disease that may lead to perforation, causing high morbidity and mortality in preterm infants. Abdominal ultrasound (AUS) has been shown to provide benefits in diagnosing and managing NEC in recent years. This study focused on the utility of AUS in the diagnosis and evaluation of surgical NEC. In this retrospective study, available data of the patients diagnosed from January 2019 to June 2022 were reviewed. The sensitivity and specificity of AUS in diagnosing a perforation were analyzed. Typical cases for the application of AUS in monitoring and evaluating the progression, complications, and sequela of NEC were described. There were 69 neonates diagnosed with NEC and examined by AUS, of whom eight patients developed a perforation. AUS was used for diagnosing a perforation in eight patients with key features of pneumoperitoneum and/or complex ascites, allowing us to find four locations of perforation, with a sensitivity and specificity of 100%. AUS plays an important role in diagnosing and evaluating surgical NEC in newborn infants, with good sensitivity and specificity.

The Use of Conventional Lower-Frequency Color Doppler Ultrasound for Flap Planning in the Lower Extremity.

Handheld Doppler is often inaccurate in localization of perforators for pedicled and free flaps. Color Doppler ultrasound (CDU), in contrast, allows more accurate mapping and characterization of perforators to facilitate rapid flap harvest. Forty-seven flaps harvested from the lower extremity were evaluated preoperatively with CDU by a single surgeon with a conventional low-frequency ultrasound device (Philips Sparq, Cambridge, Mass). Flaps evaluated included profunda artery perforator flaps (n = 36), anterolateral thigh flaps (n = 2), pedicled propeller perforator flaps (n = 7), and toe transfers (n = 2). In all cases where a free profunda artery perforator or anterolateral thigh flap was used, the location of the dominant perforator visualized preoperatively correlated exactly with intraoperative findings. In cases where CDU was used preoperatively to locate a large perforator close to a lower extremity defect for reconstruction with a propeller perforator flap, all perforators could be used, and all flaps were successful. Preoperative CDU is particularly useful for flap planning where knowledge of the location of the dominant perforator is critical. This includes planning of thin and superthin free flaps, as well as freestyle perforator flaps. Our clinical experience suggests that this technology should be routinely adopted in certain aspects of reconstructive microsurgery.

Current practice and provision of oncoplastic breast-conserving surgery in the UK: results of the ANTHEM national practice questionnaire.

Oncoplastic breast-conserving surgery (OPBCS) may be a better option than mastectomy ± immediate breast reconstruction (IBR) for women with breast cancer but studies directly comparing the techniques are lacking. We surveyed UK breast units to determine the current practice of OPBCS to inform the design of a future comparative study. An electronic survey was developed to explore the current practice of OPBCS. This included the local availability of volume displacement and/or replacement techniques; number of cases performed; contraindications and approach to contralateral symmetrisation. Summary data for each survey item were calculated and overall provision of care examined. 58 UK centres completed the survey, including 43 (74%) stand-alone breast and 15 (26%) combined breast/plastics units. Over 40% of units (n = 24) treated more than 500 cancers/year. Most units offered volume displacement techniques (TMs) (97%). Over two-thirds (n = 39. 67%) of units offered local perforator flaps (LPF). Approximately a half of units (10/19) not performing LPF were planning to introduce them in the next 12-24months. A third (n = 19, 33%) of units routinely performed simultaneous contralateral symmetrisation mostly with two-surgeon operating. There were limited oncological restrictions to OPBCS with no contraindications for multifocal cancers in most centres; 65% of units (36/55) offered OPBCS for multicentric disease. Extensive DCIS was a contraindication in a minority of units. OPBCS is widely available in the UK but contraindications and approaches to contralateral symmetrisation were variable. Work is now needed to prospectively evaluate the outcomes of OPBCS vs mastectomy ± IBR to support informed decision-making.