Absolute direction in organelle movement.

In movement analysis, correlated random walk (CRW) models often use so-called turning angles, which are measured relative to the previous movement direction. To segregate between different movement modes, hidden Markov models (HMMs) describe movements as piecewise stationary CRWs in which the distributions of turning angles and step sizes depend on the underlying state. This typically allows for the segregation of movement modes that show different movement speeds. We show that in some cases, it may be interesting to investigate absolute angles, that is, biased random walks (BRWs) instead of turning angles. In particular, while discrimination between states in the turning angle setting can only rely on movement speed, models with absolute angles can be used to discriminate between sections of different movement directions. A preprocessing algorithm is provided that enables the analysis of absolute angles in the existing R package moveHMM. In a data set of movements of cell organelles, models using not the turning angle but the absolute angle could capture interesting additional properties. Goodness-of-fit was increased for HMMs with absolute angles, and HMMs with absolute angles tended to choose a higher number of states, suggesting the existence and relevance of prominent directional changes in the present data set. These results suggest that models with absolute angles can provide important information in the analysis of movement patterns if the existence and frequency of directional changes is of biological importance.

Cold mediates maize root hair developmental plasticity via epidermis-specific transcriptomic responses.

Cold stress during early development limits maize (Zea mays L.) production in temperate zones. Low temperatures restrict root growth and reprogram gene expression. Here, we provide a systematic transcriptomic landscape of maize primary roots, their tissues, and cell types in response to cold stress. The epidermis exhibited a unique transcriptomic cold response, and genes involved in root hair formation were dynamically regulated in this cell type by cold. Consequently, activation of genes involved in root hair tip growth contributed to root hair recovery under moderate cold conditions. The maize root hair defective mutants roothair defective 5 (rth5) and roothair defective 6 (rth6) displayed enhanced cold tolerance with respect to primary root elongation. Furthermore, dehydration response element-binding protein 2.1 (dreb2.1) was the only member of the dreb subfamily of AP2/EREB transcription factor genes upregulated in primary root tissues and cell types but exclusively downregulated in root hairs upon cold stress. Plants overexpressing dreb2.1 significantly suppressed root hair elongation after moderate cold stress. Finally, the expression of rth3 was regulated by dreb2.1 under cold conditions, while rth6 transcription was regulated by dreb2.1 irrespective of the temperature regime. We demonstrated that dreb2.1 negatively regulates root hair plasticity at low temperatures by coordinating the expression of root hair defective genes in maize.

Twenty-Five Years of Progress-Lessons Learned From JMIR Publications to Address Gender Parity in Digital Health Authorships: Bibliometric Analysis.

BACKGROUND: Digital health research plays a vital role in advancing equitable health care. The diversity of research teams is thereby instrumental in capturing societal challenges, increasing productivity, and reducing bias in algorithms. Despite its importance, the gender distribution within digital health authorship remains largely unexplored. OBJECTIVE: This study aimed to investigate the gender distribution among first and last authors in digital health research, thereby identifying predicting factors of female authorship. METHODS: This bibliometric analysis examined the gender distribution across 59,980 publications from 1999 to 2023, spanning 42 digital health journals indexed in the Web of Science. To identify strategies ensuring equality in research, a detailed comparison of gender representation in JMIR journals was conducted within the field, as well as against a matched sample. Two-tailed Welch 2-sample t tests, Wilcoxon rank sum tests, and chi-square tests were used to assess differences. In addition, odds ratios were calculated to identify predictors of female authorship. RESULTS: The analysis revealed that 37% of first authors and 30% of last authors in digital health were female. JMIR journals demonstrated a higher representation, with 49% of first authors and 38% of last authors being female, yielding odds ratios of 1.96 (95% CI 1.90-2.03; P<.001) and 1.78 (95% CI 1.71-1.84; P<.001), respectively. Since 2008, JMIR journals have consistently featured a greater proportion of female first authors than male counterparts. Other factors that predicted female authorship included having female authors in other relevant positions and gender discordance, given the higher rate of male last authors in the field. CONCLUSIONS: There was an evident shift toward gender parity across publications in digital health, particularly from the publisher JMIR Publications. The specialized focus of its sister journals, equitable editorial policies, and transparency in the review process might contribute to these achievements. Further research is imperative to establish causality, enabling the replication of these successful strategies across other scientific fields to bridge the gender gap in digital health effectively.

Towards equal representation - A bibliometric analysis of authorships in Laboratory Medicine and Clinical Chemistry from the United States, Canada, and Europe (2005-2022).

Objectives: Although diversity has been demonstrated to benefit research groups, women remain underrepresented in most scientific disciplines, including Laboratory Medicine and Clinical Chemistry. In order to promote diversity and equality in scientific communities, understanding the gender distribution of authorship is crucial. Methods: This study included a total of 30,268 Web of Science-listed Clinical Chemistry and Laboratory Medicine publications from the United States of America, Canada, and the member countries of the European Federation of Clinical Chemistry and Laboratory Medicine from 2005 to 2022. In addition to the publication productivity of female and male authors over time, gender-specific publication characteristics and country-specific gender distributions of authorships were examined. Results: Overall, publications with female first authors increased by 49 % between 2005 and 2022, averaging 42 % female first authors. Eastern Europe (60 %) and Southern Europe (51 %) had particularly high proportions of female first authors. While female last authorship was the most predictive of female first authorship, with an odds ratio of 2.01 (95 % CI: 1.91-2.12, p < 0.001), only 27 % of last authors were female. Moreover, citation rate was not predictive of female first or last authorship. Conclusion: Authorship in Clinical Chemistry and Laboratory Medicine is moving towards gender parity. This trend is more pronounced for first authors than for last authors. Further research into the citations of female authors in this discipline could be a starting point for increasing the visibility of women researchers in science. Moreover, geographical differences may provide opportunities for future research on gender parity across disciplines.

Comparison of ChatGPT, Gemini, and Le Chat with physician interpretations of medical laboratory questions from an online health forum.

OBJECTIVES: Laboratory medical reports are often not intuitively comprehensible to non-medical professionals. Given their recent advancements, easier accessibility and remarkable performance on medical licensing exams, patients are therefore likely to turn to artificial intelligence-based chatbots to understand their laboratory results. However, empirical studies assessing the efficacy of these chatbots in responding to real-life patient queries regarding laboratory medicine are scarce. METHODS: Thus, this investigation included 100 patient inquiries from an online health forum, specifically addressing Complete Blood Count interpretation. The aim was to evaluate the proficiency of three artificial intelligence-based chatbots (ChatGPT, Gemini and Le Chat) against the online responses from certified physicians. RESULTS: The findings revealed that the chatbots' interpretations of laboratory results were inferior to those from online medical professionals. While the chatbots exhibited a higher degree of empathetic communication, they frequently produced erroneous or overly generalized responses to complex patient questions. The appropriateness of chatbot responses ranged from 51 to 64 %, with 22 to 33 % of responses overestimating patient conditions. A notable positive aspect was the chatbots' consistent inclusion of disclaimers regarding its non-medical nature and recommendations to seek professional medical advice. CONCLUSIONS: The chatbots' interpretations of laboratory results from real patient queries highlight a dangerous dichotomy - a perceived trustworthiness potentially obscuring factual inaccuracies. Given the growing inclination towards self-diagnosis using AI platforms, further research and improvement of these chatbots is imperative to increase patients' awareness and avoid future burdens on the healthcare system.

Comparison of the Performance of GPT-3.5 and GPT-4 With That of Medical Students on the Written German Medical Licensing Examination: Observational Study.

BACKGROUND: The potential of artificial intelligence (AI)-based large language models, such as ChatGPT, has gained significant attention in the medical field. This enthusiasm is driven not only by recent breakthroughs and improved accessibility, but also by the prospect of democratizing medical knowledge and promoting equitable health care. However, the performance of ChatGPT is substantially influenced by the input language, and given the growing public trust in this AI tool compared to that in traditional sources of information, investigating its medical accuracy across different languages is of particular importance. OBJECTIVE: This study aimed to compare the performance of GPT-3.5 and GPT-4 with that of medical students on the written German medical licensing examination. METHODS: To assess GPT-3.5's and GPT-4's medical proficiency, we used 937 original multiple-choice questions from 3 written German medical licensing examinations in October 2021, April 2022, and October 2022. RESULTS: GPT-4 achieved an average score of 85% and ranked in the 92.8th, 99.5th, and 92.6th percentiles among medical students who took the same examinations in October 2021, April 2022, and October 2022, respectively. This represents a substantial improvement of 27% compared to GPT-3.5, which only passed 1 out of the 3 examinations. While GPT-3.5 performed well in psychiatry questions, GPT-4 exhibited strengths in internal medicine and surgery but showed weakness in academic research. CONCLUSIONS: The study results highlight ChatGPT's remarkable improvement from moderate (GPT-3.5) to high competency (GPT-4) in answering medical licensing examination questions in German. While GPT-4's predecessor (GPT-3.5) was imprecise and inconsistent, it demonstrates considerable potential to improve medical education and patient care, provided that medically trained users critically evaluate its results. As the replacement of search engines by AI tools seems possible in the future, further studies with nonprofessional questions are needed to assess the safety and accuracy of ChatGPT for the general population.

Measuring capillary blood glucose concentration: Is the first blood drop really the right blood drop?

BACKGROUND: Capillary blood glucose (CBG) is fundamental for diabetes mellitus management. However, it is still unclear whether the first or the subsequent blood drops most accurately reflect patients' blood glucose levels. METHODS: 128 healthy volunteers were included in this prospective cohort study from November 2021 to December 2021. Capillary blood glucose concentrations of the first four blood drops, measured using glucose meters were compared with venous blood concentrations of the respective donors, measured using an in-lab hexokinase method. ANOVA, the Spearman correlation coefficient and Bland-Altman plots were used to analyze the data. RESULTS: The mean plasma glucose concentration was 90.46 mg/dl with an SD of ± 14.416 (5.02 ± 0.8 mmol/l). There were statistically strong correlations among the glucose concentrations of all capillary blood drops (correlation coefficients of r > 0.8). The first capillary blood drops showed the lowest mean difference to plasma blood glucose concentrations (+4.92 mg/dl; +0.27 mmol/l), followed by the third drop (+7.28 mg/dl; +0.4 mmol/l), second drop (+7.30 mg/dl; +0.4 mmol/l) and fourth drop (+8.87 mg/dl; +0.49 mmol/l). CONCLUSION: There is a strong correlation and good agreement between the different capillary blood drops, making all blood drops equally suitable for blood glucose monitoring. In practice, the given setting (clinical or patient self-monitoring) should be considered upon choosing a specific blood drop.

Outcome of a polymer-free drug-coated coronary stent in bifurcation lesions-Pilot registry with serial OCT imaging.

BACKGROUND: Polymer-free and carrier-free drug-coated stents (DCS) represent a novel therapeutic option for the treatment of coronary artery disease. The objective of this pilot registry is to evaluate the safety and efficacy of DCS implantation in bifurcation lesions. METHODS: Overall, 23 consecutive patients with 24 lesions received a Biolimus A9-coated DCS for coronary bifurcation lesions. Patients were examined with quantitative coronary angiography (QCA) and optical coherence tomography (OCT) at 3-6 months of follow-up. RESULTS: A total of 23 patients with 24 bifurcation lesions were included in this study. Nine (33.3%) lesions of eight patients revealed angiographical target lesion failure due to in-stent restenosis (ISR). In total, 19 patients with 20 bifurcation lesions were suitable for OCT analysis. A total of 2936 struts were analyzed and 14 struts (0.47%) were classified as malapposed. The mean luminal area (mm2) was not different in lesions with ISR vs. lesions with no ISR (5.07 ± 2.0 vs. 5.73 ± 1.34, p = 0.39) at follow-up. Lesions with ISR showed higher mean neointimal burden (27.11 ± 10.59 vs. 13.93 ± 9.16%, respectively; p = 0.009). All of the patients who presented with significant ISR required percutaneous re-intervention. CONCLUSIONS: We observed a high rate of DCS ISR in bifurcation lesions, possibly related to increased inflammation and neoatherosclerosis. The small size of the study warrants careful interpretation of our results. Larger trials are necessary to expand knowledge of these findings.

The impact of COVID-19 on medical students' practical skills and hygiene behavior regarding venipuncture: a case control study.

BACKGROUND: Despite their importance to current and future patient care, medical students' hygiene behaviors and acquisition of practical skills have rarely been studied in previous observational study. Thus, the aim of this study was to investigate the potential impact of the COVID-19 pandemic on medical student's hygiene and practical skills. METHODS: This case-control study assessed the effect of the COVID-19 pandemic on hygiene behavior by contrasting the practical skills and hygiene adherence of 371 medical students post the pandemic associated lockdown in March 2020 with that of 355 medical students prior to the SARS-CoV-2 outbreak. Students' skills were assessed using an objective structured clinical examination (OSCE). Their skills were then compared based on their results in hygienic venipuncture and the total OSCE score. RESULTS: During the SARS-CoV-2 pandemic, medical students demonstrated an increased level of compliance regarding hand hygiene before (prior COVID-19: 83.7%; during COVID-19: 94.9%; p < 0.001) and after patient contact (prior COVID-19: 19.4%; during COVID-19: 57.2%; p = 0.000) as well as disinfecting the puncture site correctly (prior COVID-19: 83.4%; during COVID-19: 92.7%; p < 0.001). Prior to the pandemic, students were more proficient in practical skills, such as initial venipuncture (prior COVID-19: 47.6%; during COVID-19: 38%; p < 0.041), patient communication (prior COVID-19: 85.9%; during COVID-19: 74.1%; p < 0.001) and structuring their work process (prior COVID-19: 74.4%; during COVID-19: 67.4%; p < 0.024). CONCLUSION: Overall, the COVID-19 pandemic sensitized medical students' attention and adherence to hygiene requirements, while simultaneously reducing the amount of practice opportunities, thus negatively affecting their practical skills. The latter development may have to be addressed by providing additional practice opportunities for students as soon as the pandemic situation allows.

Symbiont demand guides resource supply: leaf-cutting ants preferentially deliver their harvested fragments to undernourished fungus gardens.

Leaf-cutting ants are highly successful herbivores in the Neotropics. They forage large amounts of fresh plant material to nourish a symbiotic fungus that sustains the colony. It is unknown how workers organize the intra-nest distribution of resources, and whether they respond to increasing demands in some fungus gardens by adjusting the amount of delivered resources accordingly. In laboratory experiments, we analyzed the spatial distribution of collected leaf fragments among nest chambers in Acromyrmex ambiguus leaf-cutting ants, and how it changed when one of the fungus gardens experienced undernourishment. Plant fragments were evenly distributed among nest chambers when the fungal symbiont was well nourished. That pattern changed when one of the fungus gardens was undernourished and had a higher leaf demand, resulting in more leaf discs delivered to the undernourished fungus garden over at least 2 days after deprivation. Some ants bypassed nourished gardens to directly deliver their resource to the chamber with higher nutritional demand. We hypothesize that cues arising from that chamber might be used for orientation and/or that informed individuals, presumably stemming from the undernourished chamber, may preferentially orient to them.

Deterioration in hygiene behavior among fifth-year medical students during the placement of intravenous catheters: a prospective cohort comparison of practical skills.

BACKGROUND: The American Association of Medical Colleges has defined peripheral intravenous cannulation as one of the eight practical skills that a medical student should possess upon graduation. Since following a standard hygiene protocol can reduce the rate of complications such as bloodstream infections, the medical student's compliance to hygienic standards is highly relevant. METHODS: This unicentric longitudinal cohort study included 177 medical students undergoing OSCE 1 in the winter semesters 2016/2017 and 2017/2018 as well as OSCE 2 during the winter semesters 2018/2019 and 2019/2020 at the University of Cologne. Their performance in peripheral intravenous cannulation was rated by trained student supervisors using a scaled 13-item questionnaire and compared between OSCE 1 and OSCE 2. RESULTS: Overall, a decline in the correct placement of peripheral intravenous catheters was observed among advanced medical students during OSCE 2 (mean total score: 6.27 ± 1.84) in comparison to their results in OSCE 1 (mean total score: 7.67 ± 1.7). During OSCE 2, the students were more negligent in regard to hygienic behavior, such as disinfection of the puncture site as well as hand disinfection before and after venipuncture. Their patients were also less likely to be informed about the procedure as compared to OSCE 1. CONCLUSIONS: An unsatisfying performance in regard to peripheral intravenous cannulation was observed in medical students with hygiene compliance deteriorating between the third and fifth year of their study. Thus, we promote an extension of practical hygiene and stress management training in medical school to reduce complications associated with intravenous catheters, such as bloodstream infections.

Comparison of Resting Full-Cycle Ratio and Fractional Flow Reserve in a German Real-World Cohort.

Objective: The aim of this study was to evaluate non-hyperemic resting pressure ratios (NHPRs), especially the novel "resting full-cycle ratio" (RFR; lowest pressure distal to the stenosis/aortic pressure during the entire cardiac cycle), compared to the gold standard fractional flow reserve (FFR) in a "real-world" setting. Methods: The study included patients undergoing coronary pressure wire studies at one German University Hospital. No patients were excluded based on any baseline or procedural characteristics, except for insufficient quality of traces. The diagnostic performance of four NHPRs vs. FFR ≤ 0.80 was tested. Morphological characteristics of stenoses were analyzed by quantitative coronary angiography. Results: 617 patients with 712 coronary lesions were included. RFR showed a significant correlation with FFR (r = 0.766, p < 0.01). Diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of RFR were 78% (95% confidence interval = 75; 81), 72% (65; 78), 81% (77; 84), 63% (57; 69), and 86% (83; 89). Relevant predictors for discordance of RFR ≤ 0.89/FFR > 0.8 were LAD lesions, peripheral artery disease, age, female sex and non-focal stenoses. Predictors for discordance of RFR > 0.89/FFR ≤ 0.8 included non-LCX lesions, percent diameter stenosis and previous percutaneous coronary intervention in the target vessel. RFR and all other NHPRs were highly correlated with each other. Conclusion: All NHPRs have a similar correlation with the gold standard FFR and may facilitate the acceptance and implementation of physiological assessments of lesion severity. However, we found ~20% discordant results between NHPRs and FFR in our "all-comers" German cohort.

Thermal imaging for microvascular free tissue transfer monitoring: Feasibility study using a low cost, commercially available mobile phone imaging system.

BACKGROUND: The use of infrared thermography to evaluate the perfusion of tissue flaps have been studied. This study aims to evaluate the utility of thermal imaging for flap monitoring with a low-cost, readily available smartphone imaging device. METHODS: Adult subjects who underwent head and neck reconstruction using a microvascular free flap with a cutaneous paddle were recruited. Thermal images were taken of the free flap before, during and after anastomosis. Thermal images were analyzed by measuring the average flap temperature minus the average surrounding tissue temperature (dT). RESULTS: Twenty-one patients were enrolled. The mean dT for flaps intraoperatively prior to anastomosis was -11.47 °F. For 20 patients, dT averaged between -0.30 to 0.12 °F. One flap was inadequately perfused and dT was found to be -4.35 °F. CONCLUSIONS: Low cost, mobile smartphone devices such as the thermal camera may provide an objective method of monitoring microvascular free flaps. LEVEL OF EVIDENCE: 2 Prospective Cohort Study.

Management of a Laryngeal Venous Malformation With Nd:YAG Laser and Bleomycin Sclerotherapy.

Literature describing neodymium:yttrium-aluminum-garnet (Nd:YAG) photocoagulation and sclerotherapy for laryngeal venous malformations (VMs) is sparse. Here we present a case in which an extensive laryngeal VM in a 28-year-old female was managed through a combination of four serial Nd:YAG laser photocoagulation sessions and four bleomycin injections over the course of 2 years. The treatment plan resulted in resulted in noticeable lesion ablation, mucosalization, and significant improvement in symptoms. To our knowledge, this case is the first instance of bleomycin injection specifically into a laryngeal VM reported in the English medical literature. Laryngoscope, 130:2199-2201, 2020.

Gender Trends in Authorship of Original Otolaryngology Publications: A Fifteen-Year Perspective.

OBJECTIVE: To examine trends in female author representation within original otolaryngology research between 2000 and 2015. METHODS: Original research articles published in 11 otolaryngology journals were analyzed for 2000, 2003, 2006, 2009, 2012, and 2015. The genders of the first and last authors for each article were recorded. Overall female authorship was calculated by summing the numbers of the first, last, and both first and last female-authored articles. Student t test and Cochran-Armitage trend test were utilized to determine significance between years and groups. RESULTS: Of the 9,623 research articles published during 5 representative years, 223 were excluded due to one or more gender-indeterminate authors. Female first authorship exhibited a significant upward trend from 2000 to 2015 (P < 0.0001), as did the proportion of literature with female first and last authors (P < 0.0001). Although female senior authorship in literature with an impact factor (IF) greater than 2 did not increase significantly (10.0% in 2000 to 10.1% in 2015; P = 0.738), this metric did increase significantly just within journals with an IF between 1 and 2 (9.7%-12.3%, P = 0.036). The proportion of articles with a female author in the first, last, or both positions increased from 28% to 39% (P < 0.0001). CONCLUSION: Increasing female representation in otolaryngology literature may reflect the rising proportion of women within otolaryngology as well as greater mentorship availability. Despite these auspicious strides, female-authored articles nonetheless represent a smaller proportion of the literature, and female senior authors remain a stark minority. Future studies should identify the barriers to female access and advancement within the field. LEVEL OF EVIDENCE: III Laryngoscope, 130:2126-2132, 2020.

Behavioral analysis of HPV+ oropharyngeal cancer: Do you know your patients?

OBJECTIVE: Evaluate the epidemiologic makeup of a population of HPV+ OPSCC patients treated at one institution over approximately a decade. STUDY DESIGN: Prospective survey study of HPV+ OPSCC treated between 2007 and 2016. SETTING: Mount Sinai Health System SUBJECTS AND METHODS: Patients aged 18+ who underwent treatment for HPV+ OPSCC. 223 patients were asked to complete a health survey including substance use and sexual history in order to specifically characterize the social behaviors of patients with HPV + OPSCC. RESULTS: Eighty-two patients responded, 70 male (85.4%) and 12 female (14.6%). While half of patients were nonsmokers, 18.3% had a smoking history of <15 pack years, and 32.9% had a 15+ pack-year smoking history. Nearly 25% reported significant drinking history (3+ drinks/day). Males had an average of 18 lifetime sexual partners, and females had 7 partners. Eight patients reported >100 sexual partners. CONCLUSIONS: HPV+ OPSCC was more prevalent in white males with a high number of lifetime sexual partners, as expected. Careful evaluation revealed other findings of significance that are not generally associated with this population. Half of our patients had significant historical tobacco and alcohol consumption. One quarter of patients had a history of another malignancy. These findings highlight the importance of taking a comprehensive history when determining appropriate treatment or designing future de-escalation trials in HPV+ OPSCC.

TGF-ß enhances the cytotoxic activity of Vδ2 T cells.

TGF-ß is a pleiotropic cytokine with multiple roles in immunity. Apart from its suppressive activity, TGF-ß is a driving cytokine in the differentiation of induced regulatory T cells (iTreg) but also in the polarization of interleukin-9 (IL-9) producing T helper 9 (Th9) T cells. Human Vδ2 expressing γδ T cells exert potent cytotoxicity towards a variety of solid tumor and leukemia/lymphoma target cells and thus are in the focus of current strategies to develop cell-based immunotherapies. Here we report that TGF-ß unexpectedly augments the cytotoxic effector activity of short-term expanded Vδ2 T cells when purified γδ T cells are activated with specific pyrophosphate antigens and IL-2 or IL-15 in the presence of TGF-ß. TGF-ß up-regulates the expression of CD54, CD103, interferon-γ, IL-9 and granzyme B in γδ T cells while CD56 and CD11a/CD18 are down-regulated. Moreover, we show that CD103 (αE/ß7 integrin) is recruited to the immunological synapse in γδ T cells. Increased cytotoxic activity of TGF-ß-exposed γδ T cells is reduced by anti-CD103 and further diminished upon additional anti-CD11a antibody treatment, pointing to a role of cellular adhesion in the enhanced cytolytic activity. Furthermore, magnetically sorted CD103-positive Vδ2 T cells exhibit superior cytolytic activity. In view of the importance of CD103 for tissue homing of lymphocytes, our results suggest that adoptive transfer of CD103-expressing Vδ2 T cells might favor their homing to solid tumors.

Schwannomas of the Frontal Sinus: Cases and Review of the Literature.

BACKGROUND: Although schwannomas are commonly found in the head and neck region, sinonasal tract involvement is extremely rare, estimated as <4%. The presence of these lesions in the frontal sinus is even less common. CASE DESCRIPTION: Two patients presented with schwannomas originating in the frontal sinus with variable degrees of extension. These patients underwent resection of the tumors via an endoscopic or combined approach. The histologic diagnosis confirmed schwannoma in both cases. CONCLUSIONS: Although these lesions have traditionally been approached through larger craniotomies and open procedures, we describe less invasive approaches for these rare frontal sinus schwannomas and demonstrate them as a valid alternative with minimal morbidity for patients.

AHNS Series: Do you know your guidelines? Perioperative antithrombotic management in head and neck surgery.

Head and neck surgeons are commonly faced with surgical patients who have underlying medical problems requiring antithrombotic therapy. It is difficult to achieve a balance between minimizing the risk of thromboembolism and hemorrhage in the perioperative period. Data from randomized, controlled trials are limited, and procedure-specific bleed rates are also difficult to pinpoint. The decision is made more difficult when patients with moderate-to-high risk for thromboembolic events undergo procedures that are high risk for bleeding. This is true for many head and neck oncologic surgeries. Furthermore, although elective procedures may be delayed for optimization of antithrombotic medication, emergent procedures cannot. Head and neck surgery often represents the most challenging of all these circumstances, given the potential risk of airway compromise from bleeding after head and neck surgery.

Impact of Flap Reconstruction on Radiotoxicity After Salvage Surgery and Reirradiation for Recurrent Head and Neck Cancer.

BACKGROUND: Recurrent head and neck malignancies remain a therapeutic challenge. Tissue transfer, in addition to defect coverage and prevention of wound complications, may potentially decrease radiotoxicity. We evaluated radiation toxicity and survival outcomes of patients who underwent salvage surgery with reirradiation, comparing primary closure to flap reconstruction. METHODS: Retrospective outcomes analysis of recurrent head and neck squamous cell carcinoma (HNSCC) patients treated with curative intent by salvage surgery (± flap reconstruction) and reirradiation from 1996 to 2011. Recurrent stage, reirradiation modality, chemotherapy use, and toxicities were evaluated. RESULTS: Of 96 patients, 59 had primary closure, whereas 37 underwent flap reconstruction (26 free, 11 pedicled). Median radiation and reirradiation doses were 66 Gy and 60 Gy, respectively. Comparing nonflap and flap patients, there was no significant difference in acute mild toxicities (100 vs. 100 %, p = 1.0) or acute severe toxicities (33.9 vs. 37.8 %, p = 0.83). Nonflap patients experienced significantly greater incidence of both late mild toxicities (81.4 vs. 54.1 %, p = 0.006) and late severe toxicities (47.5 vs. 21.6 %, p = 0.02). Overall survival at 5 years was equivalent (33.1 vs. 34.7 %, p = 0.88). Free flap patients had greater delays to postoperative reirradiation and treatment package times compared with pedicled flap patients but no meaningful difference in survival outcomes. CONCLUSIONS: Vascularized tissue potentially helps offset late toxicities associated with a second radiation course in recurrent head and neck cancer patients. In these selected patients, flap coverage may confer functional benefits and improve the long-term radiotoxicity profile.