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OBJECTIVE Time to return to work (RTW) after elective lumbar spine surgery is variable and dependent on many factors including patient, work-related, and surgical factors. The primary objective of this study was to describe the time and rate of RTW after elective lumbar spine surgery. Secondary objectives were to determine predictors of early RTW (< 90 days) and no RTW in this population. METHODS A retrospective analysis of prospectively collected data from the multicenter Canadian Spine Outcomes and Research Network (CSORN) surgical registry was performed to identify patients who were employed and underwent elective 1- or 2-level discectomy, laminectomy, and/or fusion procedures between January 2015 and December 2019. The percentage of patients who returned to work and the time to RTW postoperatively were calculated. Predictors of early RTW and not returning to work were determined using a multivariable Cox regression model and a multivariable logistic regression model, respectively. RESULTS Of the 1805 employed patients included in this analysis, 71% returned to work at a median of 61 days. The median RTW after a discectomy, laminectomy, or fusion procedure was 51, 46, and 90 days, respectively. Predictors of early RTW included male gender, higher education level (high school or above), higher preoperative Physical Component Summary score, working preoperatively, a nonfusion procedure, and surgery in a western Canadian province (p < 0.05). Patients who were working preoperatively were twice as likely to RTW within 90 days (HR 1.984, 95% CI 1.680–2.344, p < 0.001) than those who were employed but not working. Predictors of not returning to work included symptoms lasting more than 2 years, an increased number of comorbidities, an education level below high school, and an active workers’ compensation claim (p < 0.05). There were fourfold odds of not returning to work for patients who had not been working preoperatively (OR 4.076, 95% CI 3.087–5.383, p < 0.001). CONCLUSIONS In the Canadian population, 71% of a preoperatively employed segment returned to work after 1- or 2-level lumbar spine surgery. Most patients who undergo a nonfusion procedure RTW after 6 to 8 weeks, whereas patients undergoing a fusion procedure RTW at 12 weeks. Working preoperatively significantly increased the likelihood of early RTW.

Rational seven-vertex statistical model is considered. Using the fusion procedure, an explicit expression for the universal R-matrix of this model is obtained.

We introduce higher level $q$-oscillator representations for the quantum affine (super)algebras of type $C_n^{(1)},C^{(2)}(n+1)$ and $B^{(1)}(0,n)$. These representations are constructed by applying the fusion procedure to the level one $q$-oscillator representations which were obtained through the studies of the tetrahedron equation. We prove that these higher level $q$-oscillator representations are irreducible. For type $C_n^{(1)}$ and $C^{(2)}(n+1)$, we compute their characters explicitly in terms of Schur polynomials., 41 pages; Theorem 4.1 has been added, where we prove the irreducibility of the higher level $q$-oscillator representation in a uniform way. The proof is given in Appendix D

Background Anterior lumbar interbody fusion (ALIF) is a widely performed lumbar fusion procedure especially suited for treating lower lumbar degenerative disk disease, discogenic disease, and revision of failed posterior fusion. Advantages of the technique include maximizing implant size and correction of lordosis, and disadvantages include approach-related complications such as retrograde ejaculation, visceral injury, and vascular injury. Methods Transforaminal endoscopic spine surgery is an effective minimally invasive surgical approach that can be utilized to treat many complications of complex spine procedures. RESULTS Reported here are 2 cases illustrating the success of treating recurrent lumbar radiculopathy with transforaminal endoscopic spine surgery as a minimally invasive solution to an ALIF complication. Conclusions Transforaminal endoscopic spine surgery is suggested here as a possible treatment approach for lumbar radiculopathy after ALIF.

Postoperative infections after spine surgery can be frustrating for the patient and the surgeon. Particularly, in a patient with psoriasis, the altered genetic and cellular defense mechanisms result in a higher risk of infection that can be difficult to manage. We encountered a 55-year-old woman with multiple plaque psoriasis and psoriatic arthropathy for 15 years, who underwent L4-S1 navigation-assisted minimally invasive fusion procedure for symptomatic lumbar spondylosis while under perioperative systemic antipsoriatic medications. During the early postoperative period, blistering and operative site infection complicated the wound-healing process. The patient developed what appeared to be a pustular flare of psoriasis with widespread erythema and desquamating plaques over multiple areas. The wounds remained nonhealing with marginal necrosis that demanded repeated debridement procedures. Ultimately, negative-pressure dressing was the only modality that prevented the spread of infection, induced healthy granulation, and enhanced wound contraction. Such an extensive dermatological condition with superadded infection complicating wound healing after spine surgery is rarely reported. These conditions can be difficult to manage and require a multidisciplinary approach involving the surgeon, dermatologist, and infectious disease physician.

OBJECTIVE Spinal anesthesia (SA) is an alternative to general anesthesia (GA) for lumbar spine surgery, including complex instrumented fusion, although there are relatively few outcome data available. The authors discuss their experience using SA in a modern complex lumbar spine surgery practice to describe its utility and implementation. METHODS Data from patients receiving SA for lumbar spine surgery by one surgeon from March 2017 to December 2020 were collected via a retrospective chart review. Cases were divided into nonfusion and fusion procedure categories and analyzed for demographics and baseline medical status; pre-, intra-, and postoperative events; hospital course, including Acute Pain Service (APS) consults; and follow-up visit outcome data. RESULTS A total of 345 consecutive lumbar spine procedures were found, with 343 records complete for analysis, including 181 fusion and 162 nonfusion procedures and spinal levels from T11 through S1. The fusion group was significantly older (mean age 65.9 ± 12.4 vs 59.5 ± 15.4 years, p < 0.001) and had a significantly higher proportion of patients with American Society of Anesthesiologists (ASA) Physical Status Classification class III (p = 0.009) than the nonfusion group. There were no intraoperative conversions to GA, with infrequent need for a second dose of SA preoperatively (2.9%, 10/343) and rare preoperative conversion to GA (0.6%, 2/343) across fusion and nonfusion groups. Rates of complications during hospitalization were comparable to those seen in the literature. The APS was consulted for 2.9% (10/343) of procedures. An algorithm for the integration of SA into a lumbar spine surgery practice, from surgical and anesthetic perspectives, is also offered. CONCLUSIONS SA is a viable, safe, and effective option for lumbar spine surgery across a wide range of age and health statuses, particularly in older patients and those who want to avoid GA. The authors’ protocol, based in part on the largest set of data currently available describing complex instrumented fusion surgeries of the lumbar spine completed under SA, presents guidance and best practices to integrate SA into contemporary lumbar spine practices.

Minimally invasive lumbar transforaminal interbody fusion (MIS TLIF) has become the most commonly performed lumbar fusion procedure. There are multiple variables such as bone graft properties, use of rhBMP (recombinant human bone morphogenic protein), interbody cage properties, image guidance techniques, etc., that may impact the outcomes and fusion rates. Radiation exposure to the patient as well as to the operating team is an important concern. The minimally invasive anterior approaches for lumbar fusion with ability to insert larger cages and achieve better sagittal correction have added another option in management of lumbar degenerative deformities. A literature review of recent studies and systematic reviews on different aspects impacting the outcomes of MIS TLIF has been done to define the present status of the procedure in this narrative review. Iliac crest bone graft can help achieve very good fusion rate without significantly increasing the morbidity. RhBMP is most potent enhancer of fusion and the adverse effects can be avoided by surgical technique and using lower dose. The use of navigation techniques has reduced the radiation exposure to patient and the surgeons but the benefit seems to be significant only in long segment fusions.

We propose a novel algorithm for multi-exposure fusion (MEF). This algorithm decomposes image patches with the DCT transform. Coefficients from patches with different exposure are combined. The luminance and chrominance of the different images are fused separately. The algorithm adapts to dynamic sequences in order to avoid ghosting effects. The initial sequence is processed to be made static before applying the fusion procedure. Experiments with several data sets show that the proposed algorithm performs better than state-of-the-art.

Analysis of National Inpatient Sample (NIS), 2004 to 2015.Describe recent trends in US rates of lumbar fusion procedures and associated costs, by surgical indication.Spinal fusion is appropriate for spinal deformity and instability, but evidence of effectiveness is limited for primary disc herniation and spinal stenosis without instability. It remains controversial for treatment of axial pain secondary to degenerative disc disease. There are potential non-instability, non-deformity indications for fusion surgery, including but not limited to severe foraminal stenosis and third-time disc herniation.Elective lumber fusion trends were reported using Poisson regression, grouped by indication as degenerative scoliosis, degenerative spondylolisthesis, spinal stenosis, disc herniation, and disc degeneration. Generalize linear regression was used to estimate trends in hospital costs, adjusted for age, sex, indication, comorbidity, and inflation.Volume of elective lumbar fusion increased 62.3% (or 32.1% per 100,000 US adults), from 122,679 cases (60.4 per 100,000) in 2004 to 199,140 (79.8 per 100,000) in 2015. Increases were greatest among age 65 or older, increasing 138.7% by volume (73.2% by rate), from 98.3 per 100,000 (95% confidence interval [CI] 97.2, 99.3) in 2004 to 170.3 (95% CI 169.2, 171.5) in 2015. Although the largest increases were for spondylolisthesis (+47,390 operations, 111%) and scoliosis (+16,129 operations, 186.6%), disc degeneration, herniation, and stenosis combined to accounted for 42.3% of total elective lumbar fusions in 2015. Aggregate hospital costs increased 177% during these 12 years, exceeding $10 billion in 2015, and averaging more than $50,000 per admission.While the prevalence of spinal pathologies is not known, the rate of elective lumbar fusion surgery in the United States increased most for spondylolisthesis and scoliosis, indications with relatively good evidence of effectiveness. The proportion of fusions coded for indications with less evidence of effectiveness has slightly decreased in the most recent years.3.

Objectives Percutaneous transfacet screw fixation (pTSF) is a minimally invasive posterior fixation technique supplementing oblique lateral interbody fusion (OLIF) for lumbar spinal disorders. Accurate screw insertion is difficult to achieve and technically demanding under 2-D fluoroscopy. Recently developed robot-assisted spinal surgery demonstrated a high level of accuracy of pedicle screw insertion and a low complication rate. No published study has reported this combination technique. The aim of our study was to evaluate the accuracy and safety properties of the combination of both minimally invasive techniques: robot-assisted pTSF supplementing the OLIF procedure. Methods This was an experimental and prospective study. Selected consecutive patients with lumbar degenerative disorders received robot-assisted pTSF supplementing the OLIF procedure using the TianJi Robot system operated by one senior surgeon from March to October 2018. The accuracy of screw insertion and perioperative screw-related complications were evaluated. Assessment of the accuracy of screw insertion included intraoperative robotic guidance accuracy and incidence of screw encroachments. Intraoperative robotic guidance accuracy referred to translational and angular deviations of screws, which were assessed by comparing the planned and actual screw trajectories guided by the robot on reconstructed images using TianJi Robot Planning Software. Screw encroachments were evaluated on postoperative CT images and classified by a grading system (A, excellent; B, good; C, poor). Screw-related complications including intraoperative pin skidding, screw malposition and adjustment, together with postoperative neurological symptoms that correlated with screw malposition were recorded. Results Ten patients, with an average age of 60.2 years, were selected and recruited in this study. All cases were degenerative lumbar spinal disorders, out of which there were 6 cases of Meyerding Grade I degenerative spondylolisthesis. Twenty-four transfacet screws were inserted by robotic assistance. Instrumented levels included nine segments at L4-5 level and three segments at L3-4 level. Two patients had both L4-5 and L3-4 level fixation. The average surgical time was 3.3 h (SD, 0.8 h). The mean blood loss was 90 mL (SD, 32 mL). Intraoperative guidance accuracy showed 1.09 ± 0.17 mm (ranging from 0.75 to 1.22 mm) translational deviation and 2.17° ± 0.39° (ranging from 1.47° to 2.54°) angular deviation. The gradings of screw encroachment were: 17 screws (71%) with Grade A, 6 screws (25%) with Grade B, and 1 screw (4%) with Grade C. Only one pin skidding occurred intraoperatively and revised subsequently. No postoperative neurological complications were found. Conclusion Our preliminary study of robot-assisted pTSF supplementing the OLIF procedure showed a high level of accuracy for screw insertion and this minimally invasive combination technique was found to be a feasible and safe procedure.

Postsurgical spine imaging actually commences with the preoperative and perioperative imaging examinations that are performed before and during the patient's surgical procedure, respectively. It is in this context that postsurgical spine imaging examinations are best evaluated with a better appreciation of the changes, sometimes dramatic, that can occur following spine surgery. Careful follow-up is the rule in spine surgery, and these patients will have multiple imaging examinations over time. Some studies are performed immediately due to possible complications or exacerbation of pain symptoms, whereas others are used to assess the status of a fusion procedure. In any case it is prudent to always be aware of the overlap between the "normal" or expected imaging findings in the postoperative spine and potential pathologic processes that are developing at the postsurgical site. Additionally, a basic understanding of common spine surgical techniques and approaches is paramount toward rendering a thoughtful analysis. In this chapter, the authors discuss these imaging findings in the setting of the most commonly performed spine surgeries and emphasize the importance of active communication between the radiologist and spine surgeon.

Background Giant cell tumor (GCT) of bone is a benign, aggressive tumor of bone and occurs commonly around the knee and distal radius. GCT of bone rarely occurs in hand. In hand, metacarpals are the most common site and there have been only a few case reports of GCT of the carpal bone. In hand, these tumors are very aggressive and these have a high tendency to recur after intralesional curettage. No long-term study is available for choosing an appropriate method of treatment for these tumors in hand. Case Description Herein, we report a case of GCT of the bone involving triquetrum which was managed by excision of triquetrum and scaphoid bone. The reconstruction of the wrist was done through limited carpal fusion, by doing three corner fusion of the wrist. At 2 years after surgery, the patient was asymptomatic and radiographs revealed fusion of lunocapitate and lunohamate joints with no evidence of recurrence. Literature review Current literature regarding GCT of triquetrum includes case reports that are reviewed in this report. Clinical Relevance This case illustrates the successful treatment of GCT of triquetrum, which is a rare tumor. Three-corner fusion is a reliable and reproducible procedure that has been used for other arthritic conditions. The use of three corner fusion procedure can be extended to GCT of carpal bones. It has been a motion-preserving alternative to proximal row carpectomy.

Background: Complication rates following occipitocervical and atlanto-axial fusion are high. While methods to fuse the upper cervical spine levels have evolved, complication rates and surgical survivorship of occipitocervical fusion versus atlanto-axial fusion are incompletely understood. Methods: The PearlDiver Research Program (www.pearldiverinc.com) was used to identify patients undergoing primary occipitocervical or atlanto-axial fusion between 2007 and 2017. Incidence of each fusion procedure was studied across time. Multivariable logistic regression was used to compare 30-day readmission, 30-day medical complications, and post-operative opioid utilization at 1, 3, 6, and 12 months between cohorts, controlling for age, gender, Charlson Comorbidity Index (CCI), and indication for surgery. Risk of revision was compared through Cox-proportional hazards modeling, Kaplan-Meier survival, and log-rank test. Results: Cohorts of 483 occipitocervical fusions and 737 atlanto-axial fusions were examined. From 2008 to 2016, incidence of occipitocervical fusion rose 55.9%, whereas atlanto-axial fusion rose 21.6%. A greater percentage of atlanto-axial fusions were due to trauma (69.9% vs. 50.5%), whereas a greater percentage of occipitocervical fusions were due to degenerative disease (41.6% vs. 29.4%) (p = 0.0161). Total 30-day complications were seen in 40.9% of occipitocervical fusion patients compared to 26.3% of atlanto-axial fusion patients (aOR=2.06, p < 0.0001). Risk of surgical site infection was increased (aOR=2.59, p = 0.0075). Kaplan Meier survival analysis and Cox-proportional hazards demonstrated greater risk of revision following surgery for occipitocervical fusion (log rank: p < 0.0001, aHR=2.66, 95%CI 1.73–4.10, p < 0.0001). Conclusions: Rates of occipitocervical and atlanto-axial fusion are rising, while complication and revision surgery rates remain high, with occipiticervical fusion leading to higher rates even after controlling for patient characteristics and surgical indication. Spine surgeons should be cautious when considering fusion of the occipitocervical levels if atlanto-axial fusion could be performed safely and provide adequate stabilization to treat the same pathology.

International audience; The fusion of multiple segmentations aims to improve their accuracy in order to make them exploitable. However, conflicts may appear. In this paper, two conflict-management models are proposed for the fusion of complementary segmentations. This conflict-management and fusion procedure, integrated into the SAIAD project, carries out the fusion of deformed kidneys and nephroblastoma using the combination of six independent methods. These methods are based on different criteria, like the adjacent segmented slices, the variation of information, the Dice, the neighbouring labels, the pixel intensity by scanner images, and the fully connected CRFs. The performances of our fusion models was evaluated on 139 scans for three patients with nephroblastoma, and the results demonstrate its effectiveness and the improvement of the resulting segmentations.

Lumbar interbody fusion is performed to treat several spinal disorders and involves the insertion of a structural graft into an intervertebral disk space to promote bony arthrodesis. Although the posterior approach to the lumbar spine was long the most frequently adopted surgical strategy to perform fusion, anterior approaches, first introduced in 1906, have recently blossomed. Patient expectations and increasing demands for shorter hospital stay and early recovery have led to more innovative surgical techniques to reduce iatrogenic injury and postoperative morbidity. Depending on the level to be treated, several approaches have been developed, each dealing with peculiar anatomic obstacles: pure anterior, oblique anterior or lateral, and transpsoas or prepsoas. These operations can be performed using miniopen or minimally invasive approaches without clear definitive evidence for approach being superior to another in terms of fusion or clinical outcomes.

Inspired by the work [PA1], in this note, we prove that a complete set of pairwise orthogonal primitive idempotents of Yokonuma-Hecke algebras can be obtained by consecutive evaluations of a certain rational function.

Inspired by the work [IMOg2], in this note, we prove that the pairwise orthogonal primitive idempotents of generic cyclotomic Birman-Murakami-Wenzl algebras can be constructed by consecutive evaluations of a certain rational function. In the appendix, we prove a similar result for generic cyclotomic Nazarov-Wenzl algebras., Comment: a work inspired by others'. If there is any reference to be neglected, please do not hesitate to contact me. Thanks!

Stochastic resonance (SR), which is characterized by the fact that proper noise can be utilized to enhance weak periodic signals, has been widely applied in weak signal detection. SR is a nonlinear parameterized filter, and the output signal relies on the system parameters for the deterministic input signal. The most commonly used index for parameter tuning in the SR procedure is the signal-to-noise ratio (SNR). However, using the SNR index to evaluate the denoising effect of SR quantitatively is insufficient when the target signal frequency cannot be estimated accurately. To address this issue, six different indexes, namely, power spectral kurtosis of the SR output signal, correlation coefficient between the SR output and the original signal, peak SNR, structural similarity, root mean square error, and smoothness, are constructed in this study to measure the SR output quantitatively. These six quantitative indexes are fused into a new synthetic quantitative index (SQI) via a back propagation neural network to guide the adaptive parameter selection of the SR procedure. The index fusion procedure reduces the instability of each index and thus improves the robustness of parameter tuning. In addition, genetic algorithm is utilized to quickly select the optimal SR parameters. The efficiency of bearing fault diagnosis is thus further improved. The effectiveness and efficiency of the proposed SQI-based adaptive SR method for bearing fault diagnosis are verified through numerical and experiment analyses.

Sequential extraction is a useful technique for assessing the potential to leach actinides from soils; however, current literature lacks uniformity in experimental details, making direct comparison of results impossible. This work continued development toward a standardized five-step sequential extraction protocol by analyzing extraction behaviors of 232Th, 238U, 239,240Pu and 241Am from lake and ocean sediment reference materials. Results produced a standardized procedure after creating more defined reaction conditions to improve method repeatability. A NaOH fusion procedure is recommended following sequential leaching for the complete dissolution of insoluble species.

Localization with high integrity is crucial for highly autonomous vehicles. This requires that the localization system send a warning to a client application when it should not be used. The concept of integrity was firstly developed for aviation applications and recently became an active research area for autonomous vehicles. GNSS information merged with dead reckoning sensors is not sufficient for lane level localization in all navigation environments. Map-aided localization with vision sensors is essential to provide redundant and complementary information. In this work, a multi-sensor data fusion method that takes advantage of a high definition (HD) map is presented and the integrity of the obtained solution is quantified. A Fault Detection and Exclusion (FDE) step is added to exclude the faulty measurements from the fusion procedure. A second step is to bound the estimation errors in the Along Track (AT) and Cross Track (CT) directions through Protection Levels (PL). For this step, the usual Gaussian distribution is replaced by a Student's distribution with an adapted degree of freedom chosen according to the navigation environment. The performance of the approach is evaluated with an experimental vehicle equipped with a camera able to detect up to four lane markings simultaneously.

Background: Manual palpation of rabbit spine levels has been used to assess fusion status. This method of testing is subject to inter-observer differences in assessment. We attempted to quantify fusion based on the amount of movement between rabbit vertebrae at the level of fusion. Methods: Rabbits were divided into three groups. The first underwent a sham surgery; the second underwent a unilateral spinal fusion; and the third underwent a bilateral spinal fusion. All groups were sacrificed at either 5- or 10-week post-procedure. Each spine was tested for fusion using standard manual palpation techniques. The spines were also placed on a specially designed apparatus and moved through 10°, 20°, and 30° of extension/flexion. Results: Out of 10 rabbits, 2 underwent sham surgery, 2 underwent a fusion procedure at L4–L5 and 6 underwent a fusion at L5–L6. We only included rabbits that underwent a L5–L6 fusion surgery. Our apparatus did not always rotate the spine the intended amount with up to 30% error. When rabbits graded as fused were compared to sham rabbits, there was a trend towards reduction in percent of overall measured angle within the fused group as compared to the sham group (8.77% vs . 13.84%, P=0.14). Conclusions: Our model attempted to quantify the amount of displacement between vertebrae during the manual palpation exam. There is a trend towards reduced measured angle between vertebrae between fused and non-fused spines and no statistically significant difference in overall measured angle between unilaterally and bilaterally fused spines.

Virtual fitting rooms are a very important tool in on-line shopping, which can save time, promote products, increase sales, and reduce number of returns. The main objective of this paper is to design an interactive virtual clothes try-on system that would make the on-line shopping process much easier, and affordable at the lowest cost possible in the local country of Jordan, which we consider as a case study of this work. The novelty of our work is that we use a cost effective RGB-D sensor, simple 3D cloth textures, and alignment/fusion procedure to build robust and interactive virtual fitting room targeted for the local market. Microsoft Kinect V2 sensor what was used in implementing the proposed system. Experimentations supported by real data from the Kinect sensor demonstrate its effectiveness and robustness. A user study was conducted among 65 Jordanian university students to evaluate the effectiveness and attitude toward using the proposed system. The study results indicate the importance and usefulness of the proposed system.

The impact of a positive sagittal vertical axis (SVA) on the surgical outcome for lumbar spinal stenosis (LSS) remains unclear, because sagittal imbalance in LSS may partly result from the tendency of patients to lean forward to reduce symptoms. Such an abnormality could be normalized by decompression surgery alone without corrective fusion. As this spontaneous correction is not well known, some surgeons perform only neural decompression in patients with positive SVA and decreased lumbar lordosis (LL), unless flatback-related symptoms are present, whereas other surgeons add corrective fusion to restore spinopelvic alignment. We systematically reviewed previous studies on this issue.PubMed, Cochrane Library, and Embase were searched for English articles on the relationship between SVA and decompression surgery for LSS. The rates of spontaneous correction in spinopelvic parameters and the impact of SVA on clinical outcomes were analyzed.The rate of spontaneous SVA correction from40-50 mm to normal values following decompression surgery alone varied from 25% to 73%. Overall, the spinopelvic parameters tended to improve postoperatively, with statistically significant changes in some series. Postoperative residual sagittal imbalance, rather than preoperative imbalance, more consistently showed a negative impact on clinical outcomes, but not on leg symptoms. For predicting postoperative sagittal imbalance, 2 studies identified the cutoff of20° for preoperative PI-LL mismatch. Another study suggested SVA80 mm as a useful value for this purpose.In LSS treated with decompression surgery alone, postoperative rather than preoperative sagittal imbalance more consistently affects clinical outcomes, particularly low back pain. This is probably because decompression usually partly improves preoperative spinopelvic sagittal malalignment. Thus, LSS, if associated with preoperative PI-LL mismatch20° and SVA80 mm, may not require additional corrective fusion procedures.

The method of image fusion for images of the same scene obtained in different spectral ranges with the formation of an integrated monochrome image is considered. The fusion method is based on the wavelet decomposition of the original images. A strategy for fusing detail coefficients by comparing the proportions of their magnitudes for all original images is proposed. The fusion procedure does not require any thresholds. The algorithm does not introduce additional distortions and collects all the necessary information from the original images. The proposed algorithm can be used in optoelectronic systems for automatic image processing.

A multi stage fusion procedure for the localization of eye and eyebrow.A remote gaze direction recognition system.We show that using the eyebrow, better gaze precision is achievable especially on the vertical direction. In this paper we investigate the accuracy of estimating a person's direction of gaze from remote imaging. The problem is addressed by a person independent, multistage fusion approach for eye landmark localization, followed by eye region analysis for actual gaze recognition. We test the proposed landmark localization system on three databases, showing superior accuracy than state of the art solutions. Finally, we show that, inspired by human perception, by incorporating the location of eyebrows, superior performance is achievable when estimating the gaze direction. Given the found results, we argue that computer vision systems for gaze recognition should mimic the human perception and incorporate the eyebrows.

We establish two versions of the fusion procedure for the walled Brauer algebras. In each of them, a complete system of primitive pairwise orthogonal idempotents for the walled Brauer algebra is constructed by consecutive evaluations of a rational function in several variables on contents of standard walled tableaux.

Advancements in surgical techniques and instrumentation have led to minimally invasive methods to achieve interbody fusion. The oblique lateral interbody fusion procedure represents a minimally invasive modification of the traditional anterolateral approach to the lumbar spine that allows quicker mobilization and less post-operative pain. The dissection plane is extraperitoneal and provides access to the discs anterior to the psoas muscle. This anterolateral corridor minimizes psoas-related injury, with early evidence of less post-operative lumbar plexus- and psoas-related morbidity, particularly at L4-5 which may be difficult to access via the direct lateral approach. This technique uniquely permits anterior access to L5-S1, which is not accessible using the lateral approach. Additional benefits of this technique include high fusion rates, indirect decompression, and deformity correction via a minimally invasive procedure. We review the history and evolution of this procedure and provide a detailed surgical technique to perform this minimally invasive psoas-sparing retroperitoneal approach to access the ventral lumbar spine.