Local Reconstruction Research Articles

In/Outside Catalytic Sites of the Pore Walls in One‐Dimensional Covalent Organic Frameworks for Oxygen Reduction Reaction

Pore channels play a decisive for mass transport in catalytic systems. However, the influences of the location of catalytic sites inside or outside of the pore walls on the performance were still under‐explored due, because it is difficult to construct sites anchored in or outside of pore walls. Herein, one‐dimensional covalent organic frameworks (COFs) with precisely anchored active sites were used to explore the effects of channels on a typical oxygen reduction reaction (ORR) catalysis. Electrocatalytic evaluations showed that single Pt sites located inside of the channels exhibited higher kinetic activity compared to those anchored outside. The in situ spectroscopic analysis revealed that local reconstruction of Pt–Cl breaking and potential‐induced anion transport occurred more effectively inside the channels. The superior anion transportability and kinetic activity of the inside‐channel active sites also facilitated *OH desorption during the ORR process outperforming their outside‐channel counterparts. The results of this study provide strategies for designing active sites in porous catalysts for heterogeneous catalysis.

In/Outside Catalytic Sites of the Pore Walls in One-Dimensional Covalent Organic Frameworks for Oxygen Reduction Reaction.

Pore channels play a decisive for mass transport in catalytic systems. However, the influences of the location of catalytic sites inside or outside of the pore walls on the performance were still under-explored due, because it is difficult to construct sites anchored in or outside of pore walls. Herein, one-dimensional covalent organic frameworks (COFs) with precisely anchored active sites were used to explore the effects of channels on a typical oxygen reduction reaction (ORR) catalysis. Electrocatalytic evaluations showed that single Pt sites located inside of the channels exhibited higher kinetic activity compared to those anchored outside. The in situ spectroscopic analysis revealed that local reconstruction of Pt-Cl breaking and potential-induced anion transport occurred more effectively inside the channels. The superior anion transportability and kinetic activity of the inside-channel active sites also facilitated *OH desorption during the ORR process outperforming their outside-channel counterparts. The results of this study provide strategies for designing active sites in porous catalysts for heterogeneous catalysis.

VILOCA: sequencing quality-aware viral haplotype reconstruction and mutation calling for short-read and long-read data.

RNA viruses exist as large heterogeneous populations within their host. The structure and diversity of virus populations affects disease progression and treatment outcomes. Next-generation sequencing allows detailed viral population analysis, but inferring diversity from error-prone reads is challenging. Here, we present VILOCA (VIral LOcal haplotype reconstruction and mutation CAlling for short and long read data), a method for mutation calling and reconstruction of local haplotypes from short- and long-read viral sequencing data. Local haplotypes refer to genomic regions that have approximately the length of the input reads. VILOCA recovers local haplotypes by using a Dirichlet process mixture model to cluster reads around their unobserved haplotypes and leveraging quality scores of the sequencing reads. We assessed the performance of VILOCA in terms of mutation calling and haplotype reconstruction accuracy on simulated and experimental Illumina, PacBio and Oxford Nanopore data. On simulated and experimental Illumina data, VILOCA performed better or similar to existing methods. On the simulated long-read data, VILOCA is able to recover on average [Formula: see text] of the ground truth mutations with perfect precision compared to only [Formula: see text] recall and [Formula: see text] precision of the second-best method. In summary, VILOCA provides significantly improved accuracy in mutation and haplotype calling, especially for long-read sequencing data, and therefore facilitates the comprehensive characterization of heterogeneous within-host viral populations.

PRIMARY CHONDROSARCOMA OF RIB: RARE NEOPLASM WITH ATYPICAL PRESENTATION

Background:Chondrosarcoma is uncommon malignant tumor of rib can have atypical presentation based on age, gender and clinical features. However, Computed Tomography is imaging modality of choice and helps aids in diagnosis and guiding treatment. Case Presentation: This was a case of 84 year old lady, who presented as a breast lump. Core needle biopsy gave the differential diagnosis Malignant phylloides with heterologous cartilaginous component, Primary chondroid sarcoma, Metaplastic carcinoma. However, imaging findings led to diagnosis of chondrosarcoma arising from right 4th rib and hence patient underwent en bloc excision of anterior chest wall with chest wall reconstruction. Final histopathology was suggestive of grade 2 chondrosarcoma with medial margin microscopically positive. Patient was kept on 2 monthly follow up after surgery without giving any adjuvant therapy or additional surgery. She was disease free at 6 months follow up. Conclusion: The incidence of rib Chondrosarcoma is rare and presents a diagnostic challenge. Surgical management with wide local excision and reconstruction remains the treatment of choice.

Angiosome-Guided Revascularization in Local Flap Reconstruction of the Foot and Ankle: Comparable Outcomes With Both Direct and Indirect Revascularization.

Among patients with critical limb ischemia and tissue loss, revascularization is an essential component for limb salvage. Local flaps of the foot and ankle remain a versatile tool in reconstructive limb salvage but is dependent on adequate arterial flow. In patients with arterial occlusive disease requiring revascularization, there is a lack of evidence in the current literature investigating on the necessity of direct arterial flow to the respective angiosome for local flaps reconstruction. Our study thereby compares the outcomes of direct (DR) and indirect (IR) revascularization for local flap success. Patients who received endovascular revascularization (ER) prior to local flap reconstruction for chronic wounds in the foot and ankle were retrospectively reviewed. IR was performed in patients where DR could not be performed. DR was defined as an intervention on the same pedicle used for the local flap. IR was defined as an intervention performed on a different angiosome than the pedicle used for the local flap. Patient demographics, Charlson Comorbidity Index (CCI), angiographic details, postoperative complications, and long-term outcomes were collected. A total of 33 patients underwent 43 local flap reconstruction with preoperative ER: 58.1% (n = 25) received DR and 41.2% (n = 18) received IR. Patients had a mean CCI of 6.7 ± 1.8, with a high prevalence of diabetes mellitus (93.9%), peripheral arterial disease (90.9%), and end-stage renal disease (33.3%) with no significant differences between groups. In the immediate postoperative period (postoperative day 0 to 12), there were no significant differences in immediate flap success (DR: 100% vs IR: 88.9%, P = 0.169) or partial flap necrosis between (DR: 0.0% vs IR: 16.7%, P = 0.066). Rates of major complications from infection (DR: 28.2% vs IR: 22.2%, P = 0.736), ischemia (DR: 4.0% vs IR: 11.1%, P = 0.562), or dehiscence (DR: 8.0% vs IR: 16.7%, P = 0.634) requiring reoperation were similar between 2 groups. Overall limb salvage rate was 84.9%, and comparable between groups (DR: 78.6% vs IR: 89.5%, P = 0.628). DR and IR achieve similar rates of limb salvage and flap success after local flap reconstruction. A multidisciplinary vasculo-plastic approach that incorporates preoperative arteriogram and revascularization should be utilized for this highly comorbid patient population to achieve optimal success and limb salvage.

Advancement Flap in Paralateronasal Defect Reconstruction.

Various techniques for local flap reconstructions of the facial region have been documented in the literature, including the advancement flap. This flap is one of the most versatile options for reconstructing various skin defects across different areas of the body. The purpose of this study is to demonstrate the safety and effectiveness of the advancement flap for reconstructing the paralateronasal region after the excision of skin cancer. The following article presents a retrospective case series of 6 patients in whom the advancement flap was used to reconstruct skin defects resulting from malignant tumor resections in the paralateronasal region. No restrictions were collected regarding etiology, location, size, age, sex, or any other patient factors. The recruited patients were treated in the Maxillofacial Surgery Unit of Floraspe Renzetti Hospital of Lanciano, and the study was conducted in collaboration with Sapienza University of Rome, from February 2023 to February 2024. All the flaps settled with no complications, and all the patients were FOD (free of disease) 6 months after surgery. So, in accordance with the literature, the advancement flap turns out to be a rapid and reliable option that could be easily applied for cutaneous defects of the face even for the oldest and/or emaciated patient.

Constrained and Unconstrained Stable Discrete Minimizations for p-Robust Local Reconstructions in Vertex Patches in the de Rham Complex

Constrained and Unconstrained Stable Discrete Minimizations for p-Robust Local Reconstructions in Vertex Patches in the de Rham Complex

A critical reflection of radiotherapy on osseous free flaps in mandibular segmental resection and immediate reconstruction in locally advanced oral squamous cell carcinoma: A cohort study

Background and purposeWith standard radiotherapy protocols after R0 resection of advanced local oral squamous cell carcinoma (OSCC) and primary reconstruction of segmental defects, a high radiation dose is applied to healthy tissue in autologous microvascular free flaps. Considering the potential consequences of flap complications and associated surgeries for patients, data is lacking on whether postoperative radiotherapy (PORT) of the flap volume is indicated at all. Materials and methodsPatients with segmental mandibular resection and immediate reconstruction with osseous free flaps due to advanced OSCC between 2012 and 2022 were analyzed retrospectively regarding overall (OS), disease-free survival (DFS), local failure-free survival (LFFS), the need for secondary surgeries as well as flap complications and compared between patients with and without PORT in a matched-pair approach with occurrence of flap complications as a primary endpoint. Results105 patients matched the inclusion criteria. The maximum follow-up period was 60 months. 68 patients received PORT. 74 patients were included in the final analysis. No case of disease recurrence inside the free flap was recorded. There were no significant differences in DFS (p = 0.21), OS (p = 0.33) and LFFS (p = 0.6) between both cohorts. Occurrence of osteoradionecrosis (p = 0.03) and bone exposure (p = 0.003) was higher in irradiated flaps. In patients with PORT, the demand for secondary surgeries due to flap complications was significantly higher (p = 0.009). Radiation doses were not increased in patients with flap ORN. ConclusionPORT is associated with higher flap complications and need for secondary surgeries in advanced stage OSCC. Given a recurrence rate of zero inside the flap without PORT and the improbability of recurrence within healthy transplanted tissue, the usefulness of applying high radiation doses to this vulnerable tissue is questioned. Further refinements of RT planning should be evaluated and tested in a RCT trial.

Multi-zone cooperative reconstruction network for off-situ monitoring of the core neutron field

Neutron field monitoring based on the ex-core detection signals is an effective means to obtain the neutron distribution when the core environment is harsh. The existed off-situ reconstruction methods of neutron fields belong to global solution, which inevitably reduces the local reconstruction accuracy of neutron field. In this paper, a novel Multi-zone Cooperative Reconstruction Network (MCRNet) is proposed based on deep learning, and the assistance and synchronous gating mechanisms are designed to realize the collaborative reconstruction between different core zones. This study performed reconstruction experiments on CLEAR-I and HBR, respectively. The results show that the average relative deviation ARD is within 2 %, and the ratio of units with a RD greater than 10 % RRD≥10% is within 6.5 %. It means that for the neutron field with different scales, the MCRNet can accurately reconstruct the neutron field of some core regions under the complex core changes.

Local Oxygen Reconstruction Enables Dual‐Ion Active Sites in Carbon Cathode for High Energy Density Sodium‐Ion Capacitors

AbstractCarbon materials are the promising cathode material for sodium‐ion capacitors (SICs) with high energy/power density, however, clarifying the evolution processes of functional groups in carbon materials and revealing their energy storage mechanisms are full of challenges. Inspired by the ancient practice of alchemy, which sought to purify Dan medicine and remove impurities through precise control of the refining temperature, the local oxygen reconstruction strategy, to alter the functional groups species in SP3‐C, is pioneeringly utilized, achieving targeted regulation of carbonyl groups with increase from 27.9 to 43.3 at%, which efficiently change the electronic structure of the carbon framework and realize the dual‐ion adsorption of Na+ and ClO4−, according well with the theoretical calculations. As expected, the obtained carbon cathode delivers a specific capacity of 145 mAh g−1, higher than that of the parent carbon material (95 mAh g−1). Impressively, the ex situ X‐ray Photoelectron Spectroscopy and in situ Raman reveals that carbonyl can act as dual‐ion active sites for Na+ and ClO4− through pseudocapacitive behavior under different voltage states. Notably, the assembled SIC using the carbonyl‐rich carbon cathode exhibits an ultrahigh energy density of 162 Wh kg−1. This work opens a novel avenue for regulating the carbonyl content of carbon materials.

Real-Time LiDAR–Inertial Simultaneous Localization and Mesh Reconstruction

In this paper, a novel LiDAR–inertial-based Simultaneous Localization and Mesh Reconstruction (LI-SLAMesh) system is proposed, which can achieve fast and robust pose tracking and online mesh reconstruction in an outdoor environment. The LI-SLAMesh system consists of two components, including LiDAR–inertial odometry and a Truncated Signed Distance Field (TSDF) free online reconstruction module. Firstly, to reduce the odometry drift errors we use scan-to-map matching, and inter-frame inertial information is used to generate prior relative pose estimation for later LiDAR-dominated optimization. Then, based on the motivation that the unevenly distributed residual terms tend to degrade the nonlinear optimizer, a novel residual density-driven Gauss–Newton method is proposed to obtain the optimal pose estimation. Secondly, to achieve fast and accurate 3D reconstruction, compared with TSDF-based mapping mechanism, a more compact map representation is proposed, which only maintains the occupied voxels and computes the vertices’ SDF values of each occupied voxels using an iterative Implicit Moving Least Squares (IMLS) algorithm. Then, marching cube is performed on the voxels and a dense mesh map is generated online. Extensive experiments are conducted on public datasets. The experimental results demonstrate that our method can achieve significant localization and online reconstruction performance improvements. The source code will be made public for the benefit of the robotic community.

High order recovery of geometric interfaces from cell-average data

We consider the problem of recovering multivariate characteristic functions u := χΩ from cell-average data on a coarse grid, motivated in particular by the accurate treatment of interfaces in finite volume schemes. While linear recovery methods are known to perform poorly, nonlinear strategies based on local reconstructions of the jump interface Γ := ∂Ω by geometrically simpler interfaces may offer significant improvements. We study two main families of local reconstruction schemes the first one based on nonlinear least-squares fitting, the second one based on the explicit computation of a polynomial-shaped curve fitting the data, which yields simpler numerical computations and high order geometric fitting. For each of them, we derive a general theoretical framework which allows us to control the recovery error by the error of best approximation up to a fixed multiplicative constant. Numerical tests in 2d illustrate the expected approximation order of these strategies. Several extensions are discussed, in particular the treatment of piecewise smooth interfaces with corners.

Comparison of Patient-Reported Outcomes after Local Flap Coverage versus Amputation for Complex Lower Extremity Trauma

Abstract Background There is a paucity of patient-reported outcomes (PROs) data in lower extremity salvage. Limb salvage can often be achieved with the use of local muscle flaps or fasciocutaneous flaps. The purpose of this study was to compare PROs of patients who underwent lower extremity salvage using local fasciocutaneous flaps or muscle flaps to lower extremity amputation. Materials and Methods The outcomes of 61 patients that underwent lower extremity local flap reconstruction (n = 33) or amputation (n = 28) between 2014 and 2020 were recorded. Chart reviews were performed to collect perioperative data. Patients were contacted via telephone for participation in the survey portion of our study. PROs were recorded utilizing both the Lower Extremity Functional Scale (LEFS) and the 36-Item Short-Form Health Survey (SF-36). Results Surveys were completed by 61 patients (response rate 59.2%). The mean time of survey after flap reconstruction or amputation was 2.7 ± 1.4 years. Recent trauma (within 90 days) was the most common indication for local flap coverage (n = 23). LEFS score and SF-36 physical functioning scores were significantly lower in patients who underwent muscle flaps compared with fasciocutaneous flaps (p = 0.021 and p = 0.022). Muscle flap patients had similar LEFS and SF-36 scores to amputation patients, while fasciocutaneous flap patients had significantly higher LEFS (p = 0.01), SF-36 physical functioning (p = 0.031), physical role functioning (p = 0.031), and emotional role functioning (p = 0.047) scores than amputation patients. Conclusion Patients who underwent local fasciocutaneous flaps for limb salvage reported higher PRO scores than those undergoing amputation, while patients undergoing muscle flaps reported outcomes similar to those undergoing amputation. PROs for muscle flap patients were significantly lower than those of fasciocutaneous flap patients. These data suggest that while fasciocutaneous and muscle flaps are both useful limb salvage procedures, fasciocutaneous flaps may confer advantages that result in improved patient-perceived outcomes. Further study is needed to better characterize outcomes in limb salvage.

CPH-Fmnet: An Optimized Deep Learning Model for Multi-View Stereo and Parameter Extraction in Complex Forest Scenes

The three-dimensional reconstruction of forests is crucial in remote sensing technology, ecological monitoring, and forestry management, as it yields precise forest structure and tree parameters, providing essential data support for forest resource management, evaluation, and sustainable development. Nevertheless, forest 3D reconstruction now encounters obstacles including higher equipment costs, reduced data collection efficiency, and complex data processing. This work introduces a unique deep learning model, CPH-Fmnet, designed to enhance the accuracy and efficiency of 3D reconstruction in intricate forest environments. CPH-Fmnet enhances the FPN Encoder-Decoder Architecture by meticulously incorporating the Channel Attention Mechanism (CA), Path Aggregation Module (PA), and High-Level Feature Selection Module (HFS), alongside the integration of the pre-trained Vision Transformer (ViT), thereby significantly improving the model’s global feature extraction and local detail reconstruction abilities. We selected three representative sample plots in Haidian District, Beijing, China, as the study area and took forest stand sequence photos with an iPhone for the research. Comparative experiments with the conventional SfM + MVS and MVSFormer models, along with comprehensive parameter extraction and ablation studies, substantiated the enhanced efficacy of the proposed CPH-Fmnet model in addressing difficult circumstances such as intricate occlusions, poorly textured areas, and variations in lighting. The test results show that the model does better on a number of evaluation criteria. It has an RMSE of 1.353, an MAE of only 5.1%, an r value of 1.190, and a forest reconstruction rate of 100%, all of which are better than current methods. Furthermore, the model produced a more compact and precise 3D point cloud while accurately determining the properties of the forest trees. The findings indicate that CPH-Fmnet offers an innovative approach for forest resource management and ecological monitoring, characterized by cheap cost, high accuracy, and high efficiency.

A breast sharing technique using the pedicled IMAP flap for delayed breast reconstruction and contralateral symmetrising mammaplasty: A case series and evolution of the surgical technique in selected patients

IntroductionThe ‘breast-sharing’ procedure uses the disposable tissue as a flap to reconstruct the post-mastectomy defect. This enables simultaneous breast reconstruction and contralateral symmetrisation without additional donor site morbidity. However, controversies related to the oncological safety of this procedure have prevented its widespread uptake. We aim to present this technique based on a pedicled internal mammary artery perforator (IMAP) flap and discuss its technical feasibility and oncological safety. Patients and methodsBetween April 2013 and May 2022, a series of 10 consecutive patients underwent a breast-sharing procedure using the pedicled IMAP flap for breast reconstruction. Clinical and surgical aspects of the breast-sharing procedure were analysed. ResultsIn all cases, the breast-sharing technique allowed for simultaneous breast reconstruction and contralateral breast symmetrisation. Immediate complications included two total venous congestions and one hematoma. Three flaps had distal flap congestion. One flap required debridement and local flap reconstruction. All flaps required fat grafting during the secondary procedures to improve breast symmetry. With an average follow-up of 5,6 years, there was no evidence of recurrent disease. All patients were satisfied to very satisfied with the aesthetic outcome of this reconstructive option. ConclusionsThe breast-sharing technique based on the IMAP flap combines breast reconstruction and contralateral symmetrisation with good aesthetic outcomes in selected patients. The flap has a high complication rate related to venous drainage. Flap design modification and using ICG imaging may reduce venous congestion. A secondary venous micro-anastomosis at the axilla is highly recommended for persistent flap congestion. The reported incidence of contralateral breast cancer is low and thus the residual tissue obtained from the contralateral breast mammaplasty can be safely used for breast reconstruction. Level of EvidenceLevel IV

National Trends in Laryngeal Laser Surgery: Comparison of Operative Versus Office-Based Procedures.

To analyze national trends in the prevalence of office-based laryngeal ablative procedures and compare those with traditional operative excisional procedures utilizing direct laryngoscopy. For years 2013-2022, the US Medicare Part B claims database was searched for Current Procedural Terminology (CPT) codes 31572 (flexible laryngoscopy with laser ablation of lesion), 31540 (operative direct laryngoscopy with excision of lesion), 31541 (operative direct microlaryngoscopy with excision of lesion), and 31545 (operative direct microlaryngoscopy with excision of lesion and local tissue flap reconstruction). For each CPT code, the total number of charges billed to the Medicare database in each calendar year was recorded and annual trends were analyzed. Biopsy procedures were not included. The annual number of office-based laser procedures (CPT 31572) remained relatively constant since the CPT code was introduced in 2017 (range: 18887-25241 procedures annually, trendline slope = +16, R2:0.02). Office-based laser procedures comprised a small portion of total laryngeal excisional procedures (range: 8.4%-12.1%). The total number of operative laryngeal excisions, billed by CPT 31540 and 31541, declined over the studied time frame (Trendline slope = -132, R2:0.93; Trendline slope = -950, R2: 0.93 respectively). Office-based laser procedures comprise a small fraction of procedures to remove laryngeal lesions. The number of office-based laser procedures has been relatively stable over the last 5 years. This finding contrasts with the prevailing health care trend toward office-based procedures. Further research is needed to understand the decrease in operative laryngeal lesion excision procedures observed over the last 10 years. 4 Laryngoscope, 2024.

Neutral Ligand Triggered Low-Dimensional Reconstruction for Improving the Efficiency and Stability of Perovskite Solar Cells.

Perovskite solar cells (PSCs) offer a potentially large-scale method for producing low-cost renewable energy. However, stability challenges currently limit their practical application. Consequently, alternative methods for increasing the PSC stability are urgently needed. Compared with three-dimensional (3D) perovskites, low-dimensional (LD) perovskites have been shown to have higher stability. In this study, a LD/3D hybrid perovskite strategy is used that involves post-treating the Cs0.05(FA0.98MA0.02)0.95Pb(I0.98Br0.02)3 perovskite with a neutral allyl 1H-imidazole-1-carboxylate (AImC) ligand. We show that this neutral organic spacer molecule has two key roles. AImC acts as a solvent and triggers localized reconstruction to produce a LD capping layer in one postprocessing step. AImC prolongs the carrier lifetime and reduces trap-assisted recombination. As a result, the PSCs containing AImC achieve a maximum power conversion efficiency (PCE) of 21.42% compared to 20.27% for the control device and show significantly decreased hysteresis. AImC also greatly increased the stability of the films and devices to air, moisture, and heat. The results of this study imply that neutral amine liquids that have the correct solvating and ligating properties have good potential to improve the PCE and stability of the PSCs.

Efficient pretraining model based on multi-scale local visual field feature reconstruction for PCB CT image element segmentation

Element segmentation is a key step in nondestructive testing of printed circuit boards (PCBs) based on computed tomography (CT) technology. In recent years, there has been rapid development of self-supervised pretraining technology that can obtain general image features without labeled samples and then uses a small amount of labeled samples to solve downstream tasks, which has good potential in PCB element segmentation. At present, a masked image modeling (MIM) pretraining model has been initially applied in PCB CT image element segmentation. However, due to the small and regular size of PCB elements such as vias, wires, and pads, the global visual field has redundancy for a single-element reconstruction, which may damage the performance of the model. Based on this issue, we propose an efficient pretraining model based on multi-scale local visual field feature reconstruction for PCB CT image element segmentation (EMLR-seg). In this model, the teacher-guided MIM pretraining model is introduced into PCB CT image element segmentation for the first time, to our knowledge, and a multi-scale local visual field extraction (MVE) module is proposed to reduce redundancy by focusing on local visual fields. At the same time, a simple four-Transformer-blocks decoder is used. Experiments show that EMLR-seg can achieve 88.6% mIoU on the PCB CT image dataset we proposed, which exceeds 1.2% by the baseline model, and the training time is reduced by 29.6 h, a reduction of 17.4% under the same experimental condition, which reflects the advantage of EMLR-seg in terms of performance and efficiency.

Pre-expanded Local Flaps: Optimal Choice for Repairing Defects Following Extensive Benign Tumor Resection in the Head and Face.

Treating extensive benign tumors of the head and face presents a longstanding challenge, necessitating efficacy at the lesion site, and postoperative esthetic considerations for the donor area. This study aims to explore the clinical outcomes of pre-expanded local flap reconstruction for extensive benign tumors of the head and face post resection. From March 2018 to March 2023, a total of 18 patients with extensive benign tumors of the head and face were admitted, including 13 cases of nevus, 2 cases of hemangioma, 2 cases of neurofibroma, and 1 case of verruca. Based on the location and size of the lesions, suitable local areas were selected for tissue expansion, and expanders were implanted for regular saline injections over 8 to 16 weeks. After reaching the desired expansion, resection of the head and facial tumors and local flap reconstruction were performed. Postoperatively, data on patients' information, tumor types, tumor area, expansion volume, postexpander complications, vascular condition after flap transfer, and donor site condition were collected. In this series of 18 patients, benign tumors of the head and face were completely repaired through 1 to 2 stages of tissue expansion surgeries. Postimplantation complications included hematoma in 1 case and infections in 2 cases, with one instance of expander infection leading to surgical failure. However, all other patients achieved adequate expansion, successful flap survival post-transfer, and experienced no other complications. Follow-up over 6 to 24 months showed no recurrence at the lesion sites, with flaps maintaining consistent color, texture, and thickness matching surrounding skin tissue. In addition, donor site healing was excellent, with no obvious surgical scars. Pre-expanded local flap reconstruction is an ideal method for repairing extensive benign tumors of the head and face postresection.

Adaptive infrared patterns for microscopic surface reconstructions

PurposeMulti-zoom microscopic surface reconstructions of operating sites, especially in ENT surgeries, would allow multimodal image fusion for determining the amount of resected tissue, for recognizing critical structures, and novel tools for intraoperative quality assurance. State-of-the-art three-dimensional model creation of the surgical scene is challenged by the surgical environment, illumination, and the homogeneous structures of skin, muscle, bones, etc., that lack invariant features for stereo reconstruction.MethodsAn adaptive near-infrared pattern projector illuminates the surgical scene with optimized patterns to yield accurate dense multi-zoom stereoscopic surface reconstructions. The approach does not impact the clinical workflow. The new method is compared to state-of-the-art approaches and is validated by determining its reconstruction errors relative to a high-resolution 3D-reconstruction of CT data.Results200 surface reconstructions were generated for 5 zoom levels with 10 reconstructions for each object illumination method (standard operating room light, microscope light, random pattern and adaptive NIR pattern). For the adaptive pattern, the surface reconstruction errors ranged from 0.5 to 0.7 mm, as compared to 1–1.9 mm for the other approaches. The local reconstruction differences are visualized in heat maps.ConclusionAdaptive near-infrared (NIR) pattern projection in microscopic surgery allows dense and accurate microscopic surface reconstructions for variable zoom levels of small and homogeneous surfaces. This could potentially aid in microscopic interventions at the lateral skull base and potentially open up new possibilities for combining quantitative intraoperative surface reconstructions with preoperative radiologic imagery.