Bilateral Hyperplasia of Mandibular Coronoid Processes in a Pediatric Patient.

Langen Beck disease, a rare idiopathic disorder, causes enlarged coronoid processes of the mandible, leading to restricted oral opening and deteriorating health. This paper presents a 10-year-old boy's case with bilateral hyperplasia of the coronoid processes (HCP), diagnosed using cranial computed tomography, severely limiting oral opening to 18 mm. Treatment involved early intraoral coronoidectomy followed by physiotherapy, yielding immediate oral opening improvement without recurrence after 1 year. Surgical timing should consider age, disease severity, and progression risk. While HCP etiology lacks conclusive evidence, genetic mutations may explain cases without identifiable causes. This case underscores the significance of timely intervention for HCP to alleviate symptoms and improve long-term outcomes, emphasizing individualized treatment strategies.

Invading new climates at what cost? Ontogenetic differences in the thermal dependence of metabolic rate in an invasive amphibian.

Global warming can either promote or constrain the invasive potential of alien species. In ectotherm invaders that exhibit a complex life cycle, success is inherently dependent on the capacity of each developmental stage to cope with environmental change. This is particularly relevant for invasive anurans, which disperse on land while requiring water for reproduction. However, it remains unknown how the different life stages respond in terms of energy expenditure under different climate change scenarios. We here quantified the oxygen uptake of frogs at rest (a proxy of the standard metabolic rate) in the aquatic phase (at the tadpole and climax, i.e. during metamorphosis, stages) and in the terrestrial phase (metamorphosed stage) at three environmental temperatures. To do so, we used marsh frogs (Pelophylax ridibundus), an amphibian with the largest invasive range within the palearctic realm and for which their adaptation to global warming might be key to their invasion success. Beyond an increase of metabolic rate with temperature, our data show variation in thermal adaptation across life stages and a higher metabolic cost during metamorphosis. These results suggest that the cost to shift habitat and face changes in temperature may be a constraint on the invasive potential of species with a complex life cycle which may be particularly vulnerable during metamorphosis.

What makes a great invader? Anatomical traits as predictors of locomotor performance and metabolic rate in an invasive frog.

Invasive species are characterized by their ability to establish and spread in a new environment. In alien populations of anurans, dispersal and fitness-related traits such as endurance, burst performance and metabolism are key to their success. However, few studies have investigated inter-individual variation in these traits and more specifically have attempted to understand the drivers of variation in these traits. Associations of anatomical features may be excellent predictors of variation in performance and could be targets for selection or subject to trade-offs during invasions. In this study, we used marsh frogs (Pelophylax ridibundus), a species that has been introduced in many places outside its native range and which is now colonizing large areas of Western Europe. We first measured the inter-individual variation in resting metabolism, the time and distance they were able to jump until exhaustion, and their peak jump force, and then measured the mass of specific organs and lengths of body parts suspected to play a role in locomotion and metabolism. Among the 5000 bootstrap replicates on body size-corrected variables, our statistical models most often selected the stomach (75.42%), gonads (71.46%) and the kidneys (67.26%) as predictors of inter-individual variation in metabolism, and the gluteus maximus muscle (97.24%) mass was the most frequently selected predictor of jump force. However, endurance was poorly associated with the anatomical traits (R2distance=0.42, R2time=0.37). These findings suggest that selection on these predictors may lead to physiological changes that may affect the colonization, establishment and dispersal of these frogs.

Shifts in the Thermal Dependence of Locomotor Performance across an Altitudinal Gradient in Native Populations of Xenopus laevis.

AbstractEctothermic species are dependent on temperature, which drives many aspects of their physiology, including locomotion. The distribution of the native populations of Xenopus laevis is characterized by an exceptional range in latitude and altitude. Along altitudinal gradients, thermal environments change, and populations experience different temperatures. In this study, we compared critical thermal limits and thermal performance curves of populations from the native range across an altitudinal gradient to test whether optimal temperatures for exertion differ depending on altitude. Data on exertion capacity were collected at six different temperatures (8°C, 12°C, 16°C, 19°C, 23°C, and 27°C) for four populations spanning an altitudinal gradient (60, 1,016, 1,948, and 3,197 m asl). Results show that the thermal performance optimum differs among populations. Populations from cold environments at high altitudes exhibit a lower optimal performance temperature than populations from warmer environments at lower altitudes. The ability of this species to change its optimal temperature for locomotor exertion across extremely different climatic environments within the native range may help explain its exceptional invasive potential. These results suggest that ectothermic species capable of adapting to broad altitudinal ranges may be particularly good at invading novel climatic areas, given their ability to cope with a wide range of variation in environmental temperatures.

Profunda Artery Perforator Flap Tongue Reconstruction: An Effective and Safe Alternative to the Anterolateral Thigh Flap.

BACKGROUND: The anterolateral thigh (ALT) perforator flap is a workhorse flap for tongue reconstruction. The authors present an alternative option using the profunda artery perforator (PAP) flap for glossectomy reconstruction compared to the ALT flap. METHODS: A retrospective review was conducted of 65 patients who underwent subtotal or total glossectomy reconstruction between 2016 and 2020 (46 ALT vs. 19 PAP flaps). Flap volume was assessed using CT scans at two different time points. Quality of life and functional outcomes were measured using the MD Anderson Symptom Inventory for head and neck cancer (MDASI-HN). RESULTS: Patients undergoing a PAP flap had significantly lower BMI compared to ALT flaps (22.7±5.0 vs. 25.8±5.1; p=0.014). Donor site and recipient site complications were similar as was the mean flap volume seven months after surgery (30.9% for ALT vs. 28.1% for PAP; p=0.93). Radiation and chemotherapy did not appear to have a significant effect on flap volume change over time. The most frequently reported high-severity items in MDASI-HN were swallowing/chewing and voice/speech for both cohorts. Patients who had reconstruction with a PAP flap had significantly better swallowing function (p=0.034). CONCLUSION: Both the PAP and ALT flaps appear to be safe and effective choices for subtotal and total tongue reconstruction. The PAP flap can serve as an alternative donor site, especially in the setting of malnourished patients with thin lateral thigh thickness undergoing reconstruction of extensive glossectomy defects.

May future climate change promote the invasion of the marsh frog? An integrative thermo-physiological study.

Climate change and invasive species are two major drivers of biodiversity loss and their interaction may lead to unprecedented further loss. Invasive ectotherms can be expected to tolerate temperature variation because of a broad thermal tolerance and may even benefit from warmer temperatures in their new ranges that better match their thermal preference. Multi-trait studies provide a valuable approach to elucidate the influence of temperature on the invasion process and offer insights into how climatic factors may facilitate or hinder the spread of invasive ectotherms. We here used marsh frogs, Pelophylax ridibundus, a species that is invading large areas of Western Europe but whose invasive potential has been underestimated. We measured the maximal and minimal temperatures to sustain physical activity, the preferred temperature, and the thermal dependence of their stamina and jumping performance in relation to the environmental temperatures observed in their invasive range. Our results showed that marsh frogs can withstand body temperatures that cover 100% of the annual temperature variation in the pond they live in and 77% of the observed current annual air temperature variation. Their preferred body temperature and performance optima were higher than the average temperature in their pond and the average air temperature experienced under the shade. These data suggest that invasive marsh frogs may benefit from a warmer climate. Broad thermal tolerances, combined with high thermal preferences and traits maximised at high temperatures, may allow this species to expand their activity period and colonise underexploited shaded habitat, thereby promoting their invasion success.

Same-Admission Microvascular Maxillofacial Ballistic Trauma Reconstruction Using Virtual Surgical Planning: A Case Series and Systematic Review.

Study Design: Retrospective case series; systematic review. Objective: It is unknown whether the use of virtual surgical planning (VSP) to facilitate same-admission microsurgical reconstruction of the mandible following acute maxillofacial ballistic trauma (MBT) is sufficient to achieve definitive reconstruction and functional occlusion. Methods: A single-center retrospective analysis was conducted for patients who underwent microsurgical reconstruction of the mandible using VSP after acute MBT. The PubMed/MEDLINE, Embase, ScienceDirect, and Scopus databases were systematically reviewed using blinded screening. Studies were evaluated via thematic analysis. Results: Five patients were treated by same-admission and microsurgical reconstruction of the mandible using VSP. We observed an average of 16.4 ± 9.1 days between initial presentation and reconstruction, an average length of stay of 51.6 ± 17.9 days, 6.2 ± 2.8 operations, and 1.6 ± 0.9 free flaps per patient. Four types and 8 total flaps were employed, most commonly the anterior lateral thigh flap (37.5%). Care yielded complete flap survival. Each patient experienced at least 1 minor complication. All patients achieved centric occlusion, oral nutrition, and an approximation of their baseline facial aesthetic. Follow up was 191.0 ± 183.9 weeks. Systematic review produced 8 articles that adhered to inclusion criteria. Consensus themes in the literature were found for clinical goal and function of VSP when practicing MBT reconstruction, yet disagreement was found surrounding optimal treatment timeline. Conclusions: Same-admission microsurgical reconstruction after MBT is safe and effective to re-establish mandibular form and function. VSP did not delay reconstruction, given the need for preparation prior to definitive reconstruction.

Ambidexterity in left-handed and right-handed individuals and implications for surgical training.

Surgical training has historically been geared toward right-handed individuals. This could cause mentors to perceive left-handed students and residents as being more difficult to train. This study examined whether differences in dexterity exist between left-handed and right-handed individuals and the implications this may have on surgical training. Recent literature suggests that surgical training may need to be updated to train left-handed students more effectively. In this prospective, crossover study, 50 right-handed and 50 left-handed individuals of varying ages and occupations were evaluated using the O'Conner Tweezer Dexterity Test. Participants were timed while they used flat-tipped forceps to pick up 1″ brass metal pins and sequentially place one pin each in 100 pinholes 1/16″ in diameter on a 21″ × 12″ board. Participants completed this exercise with their dominant hand followed by their nondominant hand. Nondominant hand dexterity was measured by dividing the nondominant hand completion time by the dominant hand completion time, with a higher percentage associated with higher ambidexterity. Using the Student's two-tailed t test, we found that left-handed individuals had an 97.2% congruence between dominant and nondominant hands while right-handed individuals had a 71.6% congruence (P < 0.001). In conclusion, our results show that left-handed individuals have a greater degree of ambidexterity than their right-handed counterparts. These results suggest that any perceived difference between left-handed and right-handed surgical residents may not be due to innate skill or dexterity, but rather a combination of external influences.

Computer-Aided Design and Manufacturing versus Conventional Surgical Planning for Head and Neck Reconstruction: A Systematic Review and Meta-Analysis.

BACKGROUND: Virtual surgical planning and computer-aided design/computer-aided manufacturing (CAD/CAM) for complex head and neck reconstruction has a number of cited advantages over conventional surgical planning, such as increased operative efficiency, fewer complications, improved osseous flap union, immediate osseointegrated dental implant placement, and superior functional and aesthetic outcomes. The authors performed a systematic review and meta-analysis of the available evidence on CAD/CAM maxillofacial reconstruction with the primary purpose of determining which approach is more efficacious. METHODS: In accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a PubMed and Embase database search was performed to identify English-language, human-subject studies of CAD/CAM-assisted head and neck reconstruction. All comparative studies were included in a meta-analysis to identify differences in operative time, ischemia time, surgical-site occurrence, microvascular complication, and partial or total flap loss between the two groups. All included studies (comparative and noncomparative) were used in the systematic review, summarizing the various flap characteristics, technical nuances, and functional and aesthetic outcomes. RESULTS: Twelve articles were included in the meta-analysis, representing 277 patients in the CAD/CAM group and 419 patients in the conventional group. CAD/CAM was associated with 65.3 fewer minutes of operating room time (95 percent CI, -72.7 to -57.9 minutes; p < 0.0001) and 34.8 fewer minutes of ischemia time (95 percent CI, -38 to -31.5 minutes; p < 0.0001). There were no significant differences in surgical-site occurrence, nonunion, flap loss, microvascular complications, or hardware-related complications. CONCLUSIONS: CAD/CAM is associated with shorter operating room and ischemia times. There are no significant differences in flap or hardware-related complications between CAD/CAM and conventional surgical planning.

Vascularized Composite Allotransplantation in Burn Reconstruction: Systematic Review and Meta-analysis.

Vascularized composite allotransplantation has been successfully employed for burn reconstruction since 2003. However, its safety in this population has been questioned due to high levels of alloimmunization from burn care-related tissue exposures. To investigate this, a systematic review of vascularized composite allotransplantation employed for burn reconstruction was conducted, evaluating literature from January 2000 to September 2019. Articles containing vascularized composite allotransplantation, composite tissue allotransplantation, and burn reconstructive surgery were included; articles without published outcomes were excluded. Observational meta-analysis of pooled mortality and acute rejection episodes relative to allograft type (face vs extremity) and reconstruction type (burn vs non-burn) was performed. Twenty-four of the 63 identified articles met the criteria for inclusion, with 5 more articles added after secondary review. To date, 152 allotransplantations have been performed in 117 patients: 45 face transplants and 107 extremity transplants. Of these, 34 (22%) were performed for burn reconstruction in 25 patients (21%) with an overall higher 1-year mortality rate (12.0% vs 1.1%, P = .030). Of these deaths, 75% received three or more simultaneous allografts. Additionally, more episodes of acute rejection occurred compared to non-burn patients (4.4 vs 2.4, P = .035). Vascularized composite allotransplantation performed for burn reconstruction was found to be associated with a greater risk of 1-year mortality and nearly twice the number of episodes of acute rejection. Future studies should seek to identify unique risk factors of burn patients undergoing this operation and evaluate the relationship between antigenic burden and surgical outcomes.

Vesicovaginal Fistula Repair by Modified Martius Flap: A Step-by-Step Surgical Technique Video.

BACKGROUND: Fistula repair in the perineal region represents a major challenge for surgeons. It is important for the medical community to facilitate and disclose these techniques. OBJECTIVE: The aim of this article was to show a stepwise approach for a direct repair and use of a Martius flap for a vesicovaginal fistula. METHODS: We show a single case performed in a patient who presented with a vesicovaginal fistula diagnosed after surgery, which did not respond to conservative management. The procedure consists of the following steps: intraoperative cystoscopy, anatomical direct repair of the fistulous tract between the bladder and vagina, and modified Martius flap. CONCLUSIONS: Martius flap is a repair technique used for complex fistula in the perineal region. It is a simple, safe, and reproducible procedure with good long-term functional and esthetic results.

Information Processing in the Brain as Optimal Entropy Transport: A Theoretical Approach.

We consider brain activity from an information theoretic perspective. We analyze the information processing in the brain, considering the optimality of Shannon entropy transport using the Monge-Kantorovich framework. It is proposed that some of these processes satisfy an optimal transport of informational entropy condition. This optimality condition allows us to derive an equation of the Monge-Ampère type for the information flow that accounts for the branching structure of neurons via the linearization of this equation. Based on this fact, we discuss a version of Murray's law in this context.

Do muscle contractile properties drive differences in locomotor performance in invasive populations of Xenopus laevis in France?

Jumping and swimming are key locomotor traits in frogs intimately linked to survival and dispersal. French populations of the frog Xenopus laevis from the invasion front are known to possess greater terrestrial locomotor endurance. Here, we tested whether individuals from the invasion front show differences in their muscle physiology that may underlie the observed whole-organism performance differences. We measured muscle contractile properties of the isolated gastrocnemius muscle in vitro, including isometric stress, activation and relaxation time, and work loop power output, both before and during a period of fatiguing contractions. We found that frogs from the centre of the range can produce tetanus force in their gastrocnemius muscle faster than animals from the periphery of the range, which could contribute to higher performance in one-off jumps. Yet, populations did not differ in muscle endurance. These results, coupled with previous work on this invasive population of Xenopus laevis, suggest that the greater stamina observed in individuals from the periphery may be more due to anatomical differences such as longer hind limbs and larger hearts along with potentially other as of yet untested physiological differences rather than differences in the mechanical properties of skeletal muscle.

Insurance Denials in Reduction Mammaplasty: How Can We Serve Our Patients Better?

BACKGROUND: Reduction mammaplasty is the standard of care for symptomatic macromastia. The process of requesting insurance coverage for reduction mammaplasty is cumbersome and potentially controversial, and insurance policies vary significantly. The goal of our analysis is to identify trends in insurance coverage rates, assess for the presence of disparities, and propose ways to increase chances of successful preauthorization. METHODS: The authors performed a retrospective review of preauthorizations for reduction mammaplasty at a single institution from 2012 to 2017. Insurance company names were deidentified. Preauthorization denial rates were assessed by year, insurance carrier, and reason for denial. Multiple regression analysis was performed to identify predictors for predetermination denial by insurance companies. RESULTS: Among 295 preauthorizations, 212 were approved (72 percent) and 83 were denied (28 percent), among which 18 were appealed, 13 successfully. Rates of insurance denials have been increasing steadily, from 18 percent to 41 percent. Medicaid had the lowest denial rates (9.3 percent), whereas private carriers denials ranged from 21.4 to 62.1 percent. In terms of reason for denial, 30 percent were because of contract exclusion, 39 percent were because of inadequate documentation or not meeting medical criteria, and 12 percent were because of inadequate predicted resection weight. Certain private insurance carriers were the only independent predictors of predetermination denial. CONCLUSIONS: Rate of preauthorization denials is high and has been increasing steadily. Insurance criteria remain arbitrary. A proper documentation and appeal process by the plastic surgeon may improve rates of insurance approval. Although resection weight does not correlate with symptom relief, predicted breast tissue resection weight continues to be critical for insurance approval.

Distant myonecrosis by atraumatic Clostridium septicum infection in a patient with metastatic breast cancer.

Clostridium septicum is an anaerobic, gram-positive bacillus known to cause myonecrosis, also known as gas gangrene, a life-threatening necrotizing soft tissue infection. Though it accounts for just 1 % of all infections attributable to Clostridia spp., C. septicum is a highly virulent and aggressive pathogen. Classic presentations of infection include bacteremia resulting in shock, myonecrosis, and vascular seeding. C. septicum-associated gas gangrene most commonly occurs in the setting of traumatic injury, but has also been reported in patients with colorectal malignancy, immunosuppression, neutropenia, and exceedingly rare in association with breast cancer. We report the case of a 56-year-old female patient with stage IV mixed lobar and ductal breast carcinoma with metastasis to the bone and liver, who presented with spontaneous C. septicum myonecrosis of the right hand. No prior traumatic injury was noted. Following amputation of the right forearm, antibiotic treatment, and multiorgan support, the patient passed following transition to palliative care. We hope to increase awareness of this relatively uncommon, though potentially deadly pathogen, as well as to discuss treatment options in patients infected with C. septicum.

Reverse Janssen Effect in Narrow Granular Columns.

When grains are added to a cylinder, the weight at the bottom is smaller than the total weight of the column, which is partially supported by the lateral walls through frictional interactions with the grains. This is known as the Janssen effect. Via a combined experimental and numerical investigation, here we demonstrate a reverse Jansen effect whereby the fraction of the weight supported by the base overcomes one. We characterize the dependence of this phenomenon on the various control parameters involved, rationalize the physical process causing the emergence of the compressional frictional forces responsible for the anomaly, and introduce a model to reproduce our findings. Contrary to prior assumptions, our results demonstrate that the constitutive relation on a material element can depend on the applied stress.

Rapid Shifts in the Temperature Dependence of Locomotor Performance in an Invasive Frog, Xenopus laevis, Implications for Conservation.

Temperature is a critical abiotic factor impacting all aspects of the biology of organisms, especially in ectotherms. As such, it is an important determinant of the potential invasive ability of organisms and may limit population expansion unless organisms can physiologically respond to changes in temperature either through plasticity or by adapting to their novel environment. Here, we studied the African clawed frog, Xenopus laevis, which has become invasive on a global scale. We compared adults from an invasive population of western France with individuals from two populations in the native range in South Africa. We measured the thermal dependence of locomotor performance in adults given its relevance to dispersal, predator escape, and prey capture. Our results show significant differences in the limits of the 80% performance breadth interval for endurance with the French population showing a left shift in its limits congruent with the colder climate experienced in France. The French invasive population was introduced only about 40 years ago suggesting a rapid shift in the thermal physiology. Given that all individuals were acclimated under laboratory conditions at 23°C for 2 months this suggests that the invasive frogs have adapted to their new environment. These data may allow the refinement of physiologically informed species distribution models permitting better estimates of future ranges at risk of invasion.

Parasitics Impact on the Performance of Rectifier Circuits in Sensing RF Energy Harvesting.

This work presents some accurate guidelines for the design of rectifier circuits in radiofrequency (RF) energy harvesting. New light is shed on the design process, paying special attention to the nonlinearity of the circuits and the modeling of the parasitic elements. Two different configurations are tested: a Cockcroft-Walton multiplier and a half-wave rectifier. Several combinations of diodes, capacitors, inductors and loads were studied. Furthermore, the parasitics that are part of the circuits were modeled. Thus, the most harmful parasitics were identified and studied in depth in order to improve the conversion efficiency and enhance the performance of self-sustaining sensing systems. The experimental results show that the parasitics associated with the diode package and the via holes in the PCB (Printed Circuit Board) can leave the circuits inoperative. As an example, the rectifier efficiency is below 5% without considering the influence of the parasitics. On the other hand, it increases to over 30% in both circuits after considering them, twice the value of typical passive rectifiers.

Allocation trade-offs impact organ size and muscle architecture in an invasive population of Xenopus laevis in Western France.

Invasive species are a global scourge and often negatively impact native species. Understanding the expansion and dispersal limits of these species is essential. As previous studies have demonstrated increased locomotor performance for populations at the edge of the range of expanding populations, studies of locomotion including the anatomical and physiological traits underlying dispersal capacity are of interest. We focus here on an invasive population of Xenopus laevis introduced in France nearly forty years ago. Previous studies have demonstrated differences in mobility between populations from the centre and the edge of the invasive range, with individuals from the range edge possessing a higher endurance capacity. We test here whether range-edge frogs show anatomical differences in organs or muscles underlying these observed differences of performance. We dissected 10 males and 10 females from central and range-edge sites (40 animals in total) and measured the mass of their organs and the mass, the length, and the physiological cross-sectional area (PCSA) of 28 hind limb muscles. Our results show anatomical differences with individuals from the range edge possessing heavier, longer and more forceful muscles. Moreover, females from the range edge had a heavier heart but lighter stomach than those of the centre of the range. Future studies comparing the morphology between native and invasive populations in other regions or for other species will be especially insightful to better understand the possible adaptive changes in invasive populations and the limits on dispersal capacity.

Redefining the Role of Resection Weight Prediction in Reduction Mammaplasty and Breaking the "One-Scale-Fits-All" Paradigm.

BACKGROUND: Reduction mammaplasty is a highly effective procedure for treatment of symptomatic macromastia. Prediction of resection weight is important for the surgeon and the patient, but none of the current prediction models is widely accepted. Insurance carriers are arbitrarily using resection weight to determine medical necessity, despite published literature supporting that resection weight does not correlate with symptomatic relief. What is the most accurate method of predicting resection weight and what is its role in breast reduction surgery? METHODS: The authors conducted a retrospective review of patients who underwent reduction mammaplasty at a single institution from 2012 to 2017. A senior biostatistician performed multiple regression analysis to identify predictors of resection weight, and linear regression models were created to compare each of the established prediction scales to actual resected weight. Patient outcomes were evaluated. RESULTS: Three-hundred fourteen patients were included. A new prediction model was created. The Galveston scale performed the best (R = 0.73; p < 0.001), whereas the Schnur scale performed the worst (R = 0.43; p < 0.001). The Appel and Descamps scales had variable performance in different subcategories of body mass index and menopausal status (p < 0.01). Internal validation confirmed the Galveston scale's best predictive value; 38.6 percent and 28.9 percent of actual breast resection weights were below Schnur prediction and 500-g minimum, respectively, yet 97 percent of patients reported symptomatic improvement or relief. CONCLUSIONS: The authors recommend a patient-specific and surgeon-specific approach for prediction of resection weight in breast reduction. The Galveston scale fits the best for older patients with higher body mass indices and breasts requiring large resections. Medical necessity decisions should be based on patient symptoms, physical examination, and the physician's clinical judgment. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, IV.