Traditional Methods Of Reconstruction Research Articles

Ulnar Collateral Ligament Repair With Internal Brace Using Linked Knotless Suture Anchors

This article presents an adaptation of the internal brace ulnar collateral ligament (UCL) repair technique using knotless suture anchors, which shows promise for improved postsurgical functionality and a shortened recovery period in patients with UCL injuries. Traditional methods of UCL reconstruction often require a lengthy 12- to 18-month recovery period, presenting a significant challenge for athletes keen to return to their sport. The modified technique uses smaller sutures and drill holes, thereby eliminating the need for larger anchors and simplifying the surgical process. Furthermore, we provide a comprehensive exploration of the rehabilitation protocol involved after surgery, which includes various phases of physical therapy and use of the “thrower’s ten” program to improve shoulder and elbow stability, strength, and mobility. This technique paves the way for a promising alternative to traditional UCL reconstruction or repair methods, with the potential to significantly enhance clinical outcomes, improve recovery times, and positively impact athletes’ lives.

The Expanding Utility of Robotic-Assisted Flap Harvest in Autologous Breast Reconstruction: A Systematic Review.

The expansion of robotic surgery has led to developments in robotic-assisted breast reconstruction techniques. Specifically, robotic flap harvest is being evaluated to help maximize operative reliability and reduce donor site morbidity without compromising flap success. Many publications are feasibility studies or technical descriptions; few cohort analyses exist. This systematic review aims to characterize trends in robotic autologous breast reconstruction and provide a summative analysis of their results. A systematic review was conducted using PubMed, Medline, Scopus, and Web of Science to evaluate robot use in breast reconstruction. Studies dated from 2006 to 2022 were identified and analyzed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Full-text, peer-reviewed, English-language, and human subject studies were included. Non-breast reconstruction articles, commentary, expert opinion, editor's letter, and duplicate studies were excluded. A total of 17 full-text articles were analyzed. The two robotic breast procedures identified were the deep inferior epigastric perforator (DIEP) and the latissimus dorsi (LD) flap. Results showed comparable complication rates and increased operative times compared to NSQIP data on their corresponding open techniques. Additional findings reported in studies included patient reported outcomes, incision lengths, and downward trends in operative time with consecutive procedures. The available data in the literature confirms that robotic surgery is a promising alternative to traditional open methods of breast reconstruction following mastectomy.

Resolving Marine-Freshwater Transitions by Diatoms Through a Fog of Gene Tree Discordance.

Despite the obstacles facing marine colonists, most lineages of aquatic organisms have colonized and diversified in freshwaters repeatedly. These transitions can trigger rapid morphological or physiological change and, on longer timescales, lead to increased rates of speciation and extinction. Diatoms are a lineage of ancestrally marine microalgae that have diversified throughout freshwater habitats worldwide. We generated a phylogenomic data set of genomes and transcriptomes for 59 diatom taxa to resolve freshwater transitions in one lineage, the Thalassiosirales. Although most parts of the species tree were consistently resolved with strong support, we had difficulties resolving a Paleocene radiation, which affected the placement of one freshwater lineage. This and other parts of the tree were characterized by high levels of gene tree discordance caused by incomplete lineage sorting and low phylogenetic signal. Despite differences in species trees inferred from concatenation versus summary methods and codons versus amino acids, traditional methods of ancestral state reconstruction supported six transitions into freshwaters, two of which led to subsequent species diversification. Evidence from gene trees, protein alignments, and diatom life history together suggest that habitat transitions were largely the product of homoplasy rather than hemiplasy, a condition where transitions occur on branches in gene trees not shared with the species tree. Nevertheless, we identified a set of putatively hemiplasious genes, many of which have been associated with shifts to low salinity, indicating that hemiplasy played a small but potentially important role in freshwater adaptation. Accounting for differences in evolutionary outcomes, in which some taxa became locked into freshwaters while others were able to return to the ocean or become salinity generalists, might help further distinguish different sources of adaptive mutation in freshwater diatoms.

Immediate Single Stage Implant-based Breast Reconstruction with or Without TIGR Mesh in Iranian Patients Undergoing Mastectomy: A Quasi-experimental Study

Background: Breast cancer is still a major contributing factor to the burden of the disease worldwide. A single-stage implant-based reconstruction (IBR) lowers tissue morbidity, thus increasing overall aesthetic outcome and patient satisfaction. Objectives: Because of the high price of ADM and the lack of insurance coverage in Iran, we aimed at examining the results of using TIGR® mesh in patients with breast cancer. Methods: This quasi-experimental study was conducted in Iran (Tehran) from 2016 to 2018. About 140 eligible patients with breast cancer were included and their information was collected and analyzed prospectively during the 3 years that they were referred to the surgery center in Tehran. The reconstruction was performed, as either direct-single staged, implant + TIGR MESH, or delayed-multistage. Patient satisfaction was calculated after 1 year of follow-up, using Body Checking Questionnaire (BCQ) by applying the VAS scale. All statistical analyses were performed at a 95% significance level, using SPSS statistical software version. (Evidence-based medicine level: Level III, a prospective cohort). Results: The results of our study showed slightly more short-term complications than other studies due to the surgical team’s first experience in the surgery. Complications were infection (7.1%), epidermal necrosis (15.9%), and severe capsular contracture (14.2%). Seven patients (6.2%) had full-thickness skin necrosis, and the prosthesis was finally removed. The use of the TIGR Mesh did not increase the rate of complications, and only 5 implant losses in this group and 2 in the tissue expander group were reported. The levels of patients’ satisfaction in IBR and delayed-multistage groups were 44.4% and 12.7%, respectively. Conclusions: Our results showed that placement of TIGR MESH for lower pole support during IBR does not increase the complication rate. Additionally, patients’ satisfaction levels increased compared to traditional methods of reconstruction.

Use of a Fibula Free Flap for Mandibular Reconstruction in Severe Craniofacial Microsomia in Children with Obstructive Sleep Apnea.

This is a retrospective study describing a multi-stage protocol for the management of severe mandibular hypoplasia in craniofacial microsomia (CFM) with accompanying obstructive sleep apnea (OSA). Patients with severe mandibular hypoplasia require reconstruction functionality and esthetical features. In the cohort, reconstructions based on free fibular flaps (FFF) may be the most effective way. Patients aged 4-17 years with severe mandibular hypoplasia were treated with FFF, which initially improved the respiratory function assessed on polysomnography (AHI). In the next stages of treatment of cases with respiratory deterioration, it was indicated to perform distraction osteogenesis (DO) of the mandible and the structures reconstructed with FFF. All surgeries were planned in accordance with virtual surgery planning VSP. The aim of the study was to prospectively assess the effectiveness of multi-stage mandibular reconstruction in craniofacial microsomia with the use of a free fibula flap in terms of improving respiratory failure due to obstructive sleep apnea (OSA). The FFF reconstruction method, performed with virtual surgical planning (VSP), is proving to be an effective alternative to traditional methods of mandibular reconstruction in patients with severe CFM with OSA.

A review of heuristic optimization techniques applied for 3D body reconstruction from anthropometric measurements

Reconstructing 3D human models has a variety of applications in areas such as entertainment, medical, manufacturing, and design. Reconstruction techniques are classified based on characteristics such as data input, devices used, and algorithms employed, in which using anthropometric measurements is one of the most widely used methods. Traditional methods of 3D human reconstruction from anthropometric measurements rely on technologies like Convolutional Neutral Network (CNN), and Linear Regression to generate an accurate model in a reasonable amount of time. This paper presents a picture of heuristic optimization methods to find the optimal solution in 3D body reconstructions from anthropometric measurements. In terms of output accuracy, the methods discussed in this paper have the potential to outperform CNN and similar technologies. Results are verified and validated on a real dataset to evaluate the performances of each method.

Penile Transplantation: Lessons Learned and Technical Considerations.

Penile vascularized composite allotransplantation is a powerful tool for penile reconstruction. Traditional methods of reconstruction utilizing free tissue and prostheses have well-known complications, can require reoperation and cannot truly emulate the natural form or function of the penis. While vascularized composite allotransplantation may alleviate these difficulties, penile transplantation carries its own ethical, surgical and medical complications. To date, the procedure has only been attempted 5 times. Broader use of this procedure requires unique surgical considerations. We present the first comprehensive, detailed review of this procedure in order to present lessons learned from both our own and the global experience. A review of published reports of penile transplant methods and outcomes was conducted to compile lessons learned from these cases. Five penile transplant cases have been reported in literature, 4 with published methodology and outcomes data. All 4 detailed unique surgical approaches and postoperative immunosuppressive regimens. Three of these cases resulted in successful sensory and functional outcomes. Though all 4 analyzed cases employed unique anastomotic and immunosuppressive approaches, 3 resulted in successful recovery of penile urinary and sexual function. Still, specific approaches used by different teams circumvented otherwise common complications, and these differences should guide future research and penile transplant cases.

A 3D Reconstruction Framework of Buildings Using Single Off-Nadir Satellite Image

A novel framework for 3D reconstruction of buildings based on a single off-nadir satellite image is proposed in this paper. Compared with the traditional methods of reconstruction using multiple images in remote sensing, recovering 3D information that utilizes the single image can reduce the demands of reconstruction tasks from the perspective of input data. It solves the problem that multiple images suitable for traditional reconstruction methods cannot be acquired in some regions, where remote sensing resources are scarce. However, it is difficult to reconstruct a 3D model containing a complete shape and accurate scale from a single image. The geometric constraints are not sufficient as the view-angle, size of buildings, and spatial resolution of images are different among remote sensing images. To solve this problem, the reconstruction framework proposed consists of two convolutional neural networks: Scale-Occupancy-Network (Scale-ONet) and model scale optimization network (Optim-Net). Through reconstruction using the single off-nadir satellite image, Scale-Onet can generate water-tight mesh models with the exact shape and rough scale of buildings. Meanwhile, the Optim-Net can reduce the error of scale for these mesh models. Finally, the complete reconstructed scene is recovered by Model-Image matching. Profiting from well-designed networks, our framework has good robustness for different input images, with different view-angle, size of buildings, and spatial resolution. Experimental results show that an ideal reconstruction accuracy can be obtained both on the model shape and scale of buildings.

CLINICAL EFFICACY COMPARATIVE EVALUATION OF THE TREATMENT METHODS OF COMBINED DEFECTS AND DEFORMITIES OF THE ZIGOMA AND ORBIT

Introduction. Zigoma and orbital defects still become an actual problem of maxilla-facial surgery due to limited possibilities to precise restoration of their complex anatomy. Functional unity of zigoma and orbit in aspects of eyeball support and protection increases requirements to reconstructive precision. The total and subtotal defects are the most difficult for reconstruction when traditional methods of reconstruction demonstrate unconvincing efficiency. Complex anatomy of zigoma and orbit, as combination of convexities, depressions limited an application of free or vascularised bone transplants for precise 3D restoration of the face. Facing this, new possibilities of reconstructed were developed, based on CAD/CAM technologies. Application of patient specific implants (PSI), designed according personal anatomy of the patient and manufactured by additive technologies, open new modalities to reconstruction in orthognatic surgery, cranioplasty and others, demonstrated promising results. So, these achievements and experience possible could be implemented for zigoma reconstruction. The aim of the study was to evaluate and compare clinical efficacy of zigoma and orbital defect treatment with traditional methods of reconstruction.
 Materials and methods. To reach this purpose, fifty-one patients, who underwent reconstruction procedures regarding zigoma defects, were enrolled to retrospective study. All of them were clinically examined before and after surgery. CT examination was performed before, 1 week and 1 year after surgery in all cases. The patients, included to the study, were divided on two groups – main and control, equal concerning age, sex and anatomical-topographic patterns of the defects. The main group consisted of 27 patients, who underwent zigoma reconstruction with PSI. The rest of the patients, treated with traditional approach (free or vascularised bone grafting, reconstructive plates or reconstruction with temporal muscle), were included to control group.
 Clinical efficacy was evaluated applying esthetical estimation of experts according to ranking scale. Additionally, frequency of complication and precision of reconstruction according to CT were analysed. Orbital volume differences were calculated for cases of orbital reconstruction.
 Results. Comparative analysis of esthetical results revealed higher quality of reconstruction in a main group. The patients did not require any further surgical procedures in 66,7% of cases, in contrast, in a control group additional interventions were indicated or performed in 85,3% of patients (p<0,05). Mean rate of aesthetic estimation by experts were 3,15+1,2 in main group and 1,96+0,8 in control. Follow-up period was longer than 12 months for both main and control groups. Mean follow-up were 20,4 ±9,3 and 26,2 ± 13,5 months respectively. During follow-up any kind of complications were observed between the patients of the main group in 14,8% of cases as well in control – 54,2 % (p=0,01). The main complication between the patients of first group was exposure of the implants, which was noted only in 3 cases, and was caused mainly extension of soft tissues above the implant or compromised soft tissue covering due to incomplete vascularisation of the flaps. At the same time the most frequently observed complications of the main group were total or partial resorption of the grafts (two cases), implant exposure (n=7) and limitation of mouth opening. Additionally, deformity of the fixators with bone fragment displacement was noted in 25,0 % cases.
 Eyeball displacement was defined in 66,7% of all cases. Mean volume difference in main group was 1,5±0,7 см3, when between patients of control it was 2,3±1,2см3 (р=0,032). The frequency of diplopia was equal for both group.
 Conclusions. The main advantage of PSI application for zigoma reconstruction is the possibility of the precise 3D restoration of its complex anatomy, renewal of the correct position of the zigoma. Relatively to the clinical tasks, PSI could be used as fixator or endoprosthesis separately or with bone graft procedures. In some clinical situations separate application of PSI as endoprosthesis may be consider as effective alternative for free tissue transfer procedures.

Craniofacial Microsurgery: An Integrated Approach to Management of Cleft and Craniofacial Syndromes, Surgical Experience, and Insights.

Ian Jackson and Jack Fisher published one of the earliest reports on microsurgical applications for craniofacial patients in 1989. Since that time, applications of craniofacial surgery and microsurgery have significantly expanded and become more refined. However, there remain certain specific clinical problems in cleft and craniofacial surgery in which traditional craniofacial methods provide variable success or suboptimal outcomes. The purpose of the current study is to share our experience using an integrated approach of craniofacial and microsurgical methods to provide optimal surgical solutions to this complex patient population. The authors performed a retrospective review of 17 patients that utilized craniofacial microsurgery in setting of cleft and craniofacial syndromes performed by the senior author from July 2013 to July 2020. 22 free flaps were performed for 17 patients. The patient age at time of flap reconstruction ranged from 10 to 48 years (mean 21.4 years). There were 8 females and 9 males. There was one total flap loss. Based on our collective experience, the authors present a comprehensive algorithm for the role of microsurgical reconstruction in cleft and craniofacial patients. There are several situations in craniofacial surgery which traditional reconstructive methods require numerous operative interventions to achieve suitable outcomes. Craniofacial Microsurgery techniques can bring in new tissue and may prevent the need to manipulate scarred and multiply operated tissues. The craniofacial surgery team should not hesitate to apply microsurgical solutions to these situations for optimal results.

Anterior Cruciate Ligament Reconstruction Using Bone–Patellar Tendon–Bone Autograft With Suture Tape Augmentation

The anterior cruciate ligament (ACL) is the most commonly injured ligament in the knee, with injury usually occurring as a result of multidirectional sports. The incidence of ACL injury has continued to increase, with most patients opting for surgery to improve stability as well as permit a return to sport. Traditional methods of ACL reconstruction can achieve this but are not without their problems, including graft rupture, residual laxity, and donor-site morbidity. There is therefore a requirement for further research into newer, innovative surgical techniques to help improve complication rates. This article describes, with video illustration, ACL reconstruction using a reduced-size bone–patellar tendon–bone autograft with suture tape augmentation. The augmentation acts as a stabilizer during the early stages of graft incorporation while resisting against reinjury during an accelerated recovery. The ability to use a reduced-size graft decreases the donor-site burden, and retention of residual native ACL tissue, when possible, may help with proprioception.

Fibrin-Based Biomaterial Systems to Enhance Anterior Cruciate Ligament Healing.

Anterior cruciate ligament (ACL) tears are a common and potentially career-ending injury, particularly for athletes and soldiers. Partial and complete ruptures of this ligament cause instability in the knee, and the ACL does not have the capacity for healing due, in part, to its position within the highly thrombolytic synovial fluid environment of the knee joint. Traditional methods of ACL reconstruction, such as graft replacement with attached bone anchors for bone integration, restore stability, but do not prevent the development of post-traumatic osteoarthritis. To enhance therapeutic treatment options, novel fibrin-based technologies and repair techniques have been recently explored and show promise for improved patient outcomes. Through modification of existing surgical methods, such as the use of fibrin glues incorporating growth factors and cells and the implementation of scaffolds containing platelet-rich plasma, platelet-rich fibrin, and other blood derivatives, surgeons are attempting to overcome the shortcomings of traditional treatments. This mini-review will detail current efforts using fibrin-based treatments and discuss opportunities to further enhance ACL healing.

Long-Term Metabolic Assessment of Cryopreserved Sternal Allograft: A Case Series

Sternal resection and reconstruction with cryopreserved allografts provides a safe alternative to traditional methods of anterior chest wall reconstruction. Despite favorable results, successful integration of the graft sternum has never been demonstrated owing to the invasiveness of bone biopsy. We describe our experience of using 18F-sodium fluoride positron emission tomography/computed tomography scans as a noninvasive method of evaluating graft integration. Seven patients underwent surgery and radiologic follow-up. Surgical indications were sternal metastases (n= 5) and sternal dehiscence (n= 2). Sternal reconstruction was performed using a cryopreserved cadaveric sternal allograft fixed in place with titanium plates and screws. Follow-up with 18F-sodium fluoride positron emission tomography/computed tomography scans was performed at 1 and 2 years after surgery. Three patients underwent total sternectomy. Two underwent partial upper sternectomy involving the manubrium, clavicle (1 patient only), and upper sternal body; and 2 had partial sternectomy of the sternal body and xiphoid process. Focal tracer accumulation occurred at the junctions between native bone and graft bone. The median maximum standardized uptake value at 1 year was 16.8 (range, 11.2 to 37.9; interquartile range, 13.6 to 19.4), and at 2 years it was 10.8 (range, 6.1 to 30.2; interquartile range, 8.9 to 15.1). In 6 cases accumulation was lower at the second scan, whereas in 1 patient the accumulation was higher at the second scan. Sternal reconstruction with cryopreserved allograft is safe and well tolerated. The 18F-sodium fluoride positron emission tomography/computed tomography scans are a useful and promising noninvasive method of demonstrating the metabolic activity of the graft and its incorporation into the host skeleton during follow-up.

Investigation of the Scattering Influence on the Quality of Image Reconstruction in Single-Photon Emission Computed Tomography in a Proportional Scattering Medium

Currently, there is only one example of a scattering medium for which the radiation scattering influence can be accurately taken into account. This is the proportional scattering medium. Single-photon emission computed tomography in a proportional scattering medium has been numerically simulated for a simple object (ellipse) and a complex object (Shepp–Logan phantom). The influence of the scattering on the reconstruction quality has been studied for various scattering medium proportionality coefficients and sizes of the object. The proportional scattering medium approximation can significantly improve the accuracy of the tomographic reconstruction in comparison with traditional analytical methods of reconstruction used in computed emission tomography.

Optimizing perioperative strategies to maximize success with prepectoral breast reconstruction.

Implant based reconstruction is still the most commonly employed method of post mastectomy reconstruction in the United States and internationally. Mastectomy techniques are improving, and adjuncts such as tissue perfusion technology and biologic implants allow for re-evaluation of traditional reconstructive methods. Subpectoral implant placement is used in a large majority of patients undergoing implant based reconstruction. However, with the advent of acellular dermal matrix (ADM), a "sling" for the expander and implant can be placed with surgical precision to create the optimal breast pocket. This has allowed for placement of the breast prosthesis in a prepectoral anatomic plane. The benefits are clear: avoidance of animation deformities and a significant decrease in pain that results from pectoralis mobilization and spasm. Here, we discuss specific techniques to avoid pitfalls and optimize aesthetic results with prepectoral breast reconstruction. Patient selection, intra-operative mastectomy flap evaluation, modifications in expander and implant fill, and technique specifics all play a critical role in this new, and rapidly growing method for implant based breast reconstruction.

Abstract 16.05 VASCULARIZED COMPOSITE ALLOTRANSPLATATION AS THERAPEUTIC STRATEGY FOR BURNED PATIENTS

Traditional reconstructive methods can fail in achieving a good functional and aesthetic outcome in patients with extensive defects, involving multiple layers of functional tissue, often necessitating numerous, and staged, surgical interventions with unsatisfactory results. Transplantation of vascularized composite allografts(VCA) opened a new, promising era in reconstructive surgery, offering a unique restorative opportunity for those complex situations. In order to extend VCA indications, further studies are needed to develop less toxic immunosuppressive regimens and possibly achieve donor-specific tolerance, the ideal situation in transplantation. Extensively burned patients, especially of the face and cervical region, having severe mutilations and also unilateral or bilateral hand amputations, like after high voltage electric injuries, present functional and aesthetic deficits, with devastating impact on their quality of life and, constituting potential candidates for receiving a vascularized composite allotransplantation, as the only reconstructive solution. With this paper, we discuss the indications and limits, from clinical and immunological perspectives, of the consideration of VCA as surgical option for burn patients with complex tissue defects, impossible to approach by conventional techniques.

Abstract 77: Outcomes Analysis of Goldilocks Mastectomy and Breast Reconstruction: The Mayo Clinic Experience

PURPOSE: The Goldilocks mastectomy procedure involves local contouring of completely autologous breast tissue created by preserving and de-epithelializing the residual mastectomy flap. This technique provides patients with an option for post-mastectomy breast reconstruction alternative to simple mastectomy without reconstruction, complex autologous flap harvesting techniques, or the use of artificial implants. The purpose of this study was to provide outcomes data for 172 Goldilocks mastectomy procedures performed at a single tertiary academic center analyzing complication rate, relevant comorbidities, and adjuvant cancer treatment impacting functional and aesthetic outcomes. This is the largest series of Goldilocks mastectomy procedures to be reported to date. METHODS: Relevant comorbidities and complication data were collected. Patients who had prior surgical procedures before presenting to our institution were designated as such. Specific breast cancer pathology and previous breast therapy were indicated. Data relevant to the Goldilocks reconstruction at our institution were collected, including laterality of procedure(s), indication (i.e. prophylactic or therapeutic), whether a tissue expander or an implant was placed at the time of the Goldilocks procedure or at any point following the procedure, the number of procedures needed for the entire reconstructive regimen, and any specific revision procedures, if needed (i.e. fat grafting, mastopexy, augmentation, or scar revision). RESULTS: A total of 95 patients underwent reconstruction with Goldilocks procedure. 82.1% (78) of cases were bilateral, and 17.8% (17) were unilateral reconstructions. Breast cancer pathology results included: DCIS 27.3% (26), LCIS 5.26% (5), stage I 11.57 (11), stage II 23.1% (22), stage III 23.1% (22), inflammatory 5.3% (5), BRCA prophylactic 11.5% (11), other 2.1% (2), and recurrent cancer 6.3% (6). Pre-operative radiation therapy was given in 7.4% (7) of patients, while post-operative radiation therapy was given to 6.31% (6) of patients. 22.1% (21) of patients received chemotherapy and 17.8% (17) received hormone therapy. Previous breast reconstruction history included implant-based reconstruction in 3.15% (3), autologous 1% (1), multiple attempts 1% (1), and failed reconstruction 1% (1). Reconstruction types included Goldilocks-only in 58% (53) of patients, Goldilocks + tissue expander in 35.8% (34), and Goldilocks with implant in 10.5% (10). 45.3% (43) of patients underwent adjuvant fat grafting, 7.3% (7) underwent concurrent mastopexy, 5.2% (5) underwent concurrent breast augmentation, and 14.7% (14) had scar revision procedures performed at the time of Goldilocks procedure. Complications included: seroma 6.3% (6), hematoma 4.2% (4), cellulitis 4.2% (4), wound dehiscence 4.2% (4), DVT/PE 1% (1), readmission 1% (1), needed take back to OR 9.5% (9), needed explant 7.4 %(7), or other complications 3.1% (3). CONCLUSION: Goldilocks mastectomy procedures are a useful adjunct in reconstruction, and can also be used in implant-based reconstruction, providing a dermal sling to build an internal bra and scaffold for the implant. Patients who have relevant medical comorbidities or who decline traditional methods of reconstruction can greatly benefit from Goldilocks mastectomy. There may be substantial utility in considering Goldilocks procedures during pre-operative planning in patient-centered care along the reconstructive ladder, as this approach has the ability of being modified with additional procedures such as fat grafting or implant placement. J. Oliver: None. A. Chaudhry: None. S. Alsubaie: None. J. Martinez-Jorge: None.

Metric three-dimensional reconstruction model from a light field and its calibration

The traditional methods of depth reconstruction from light fields have excellent performance in depth estimation; however, the depth information has nonlinear scale ambiguity. We divide the three-dimensional metric information into two easy subproblems instead of a whole question. A two-step method is proposed to obtain the metric depth and the metric lateral information, respectively. The depth model is proposed using the refocus property of the light field and the Gaussian lens formula. The model of the lateral coordinate is reasoned from the relationship between the light field in the scene and the recorded light field. Then, three calibration methods are proposed to determine these five parameters (the center position of the microlens for recovering the four-dimensional light field, the camera principal point, and the initial image distance). The experiments are conducted in our developed light field camera. The precision performance of our method is also confirmed in measuring the calibration board. When the proposed method is adopted to reconstruct the natural scene, the preferable results are obtained.

Hemi-transseptal Approach for Pituitary Surgery: A Follow-Up Study.

Objectives The hemi-transseptal (Hemi-T) approach was developed to overcome the potential drawbacks of the nasoseptal flap (NSF) in endoscopic endonasal transsphenoidal skull base surgery. In this study, we describe further refinements on the Hemi-T approach, and report long-term outcomes as compared with traditional methods of skull base reconstruction. Design A retrospective case-control study. Setting Montreal Neurological Institute and Jewish General Hospital, Montreal, Canada. Participants Patients who underwent endoscopic endonasal transsphenoidal approach to skull base pathology. Main Outcome Measures Operative time, CSF rhinorrhea, and postoperative nasal morbidity. Results A total of 105 patients underwent the Hemi-T approach versus 40 controls. Operative time was shorter using the Hemi-T technique (180.51 ± 56.9 vs. 202.9 ± 62 minutes; p = 0.048). The rates of nasal morbidity (septal perforation [5/102 vs. 6/37; p = 0.029] and mucosal adhesion [11/102 vs. 10/39 p = 0.027]), fascia lata harvest (21/100 vs. 18/39; p = 0.0028), and postoperative CSF leak rates (7/100 vs. 9/38; p = 0.006) were lower in the Hemi-T group. Conclusion Advantages of the Hemi-T approach over traditional exposure techniques include preservation of the nasal vascular pedicle, shorter operative time, reduced fascia lata harvest rates, and decreased nasal morbidity.

Hemi-transseptal Approach for Pituitary Surgery: Long Term Follow-up Study

Background: The rate of cerebrospinal fluid (CSF) leaks following endoscopic endonasal approaches to the skull base has reduced dramatically with implementation of the naso-septal flap (NSF), however at the potential cost of increased operative time and post-operative nasal morbidity. To overcome these potential drawbacks, the hemi-transeptal (Hemi-T) approach was developed. In this study we describe further refinements on the Hemi-T approach, and report long term outcomes as compared with traditional methods of skull base reconstruction.