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The early evolution of a supernova (SN) can reveal information about the environment and the progenitor star. When a star explodes in vacuum, the first photons to escape from its surface appear as a brief, hours-long shock-breakout flare1,2, followed by a cooling phase of emission. However, for stars exploding within a distribution of dense, optically thick circumstellar material (CSM), the first photons escape from the material beyond the stellar edge and the duration of the initial flare can extend to several days, during which the escaping emission indicates photospheric heating3. Early serendipitous observations2,4 that lacked ultraviolet (UV) data were unable to determine whether the early emission is heating or cooling and hence the nature of the early explosion event. Here we report UV spectra of the nearby SN 2023ixf in the galaxy Messier 101 (M101). Using the UV data as well as a comprehensive set of further multiwavelength observations, we temporally resolve the emergence of the explosion shock from a thick medium heated by the SN emission. We derive a reliable bolometric light curve that indicates that the shock breaks out from a dense layer with a radius substantially larger than typical supergiants.
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The final fate of massive stars, and the nature of the compact remnants they leave behind (black holes and neutron stars), are open questions in astrophysics. Many massive stars are stripped of their outer hydrogen envelopes as they evolve. Such Wolf-Rayet stars1 emit strong and rapidly expanding winds with speeds greater than 1,000 kilometres per second. A fraction of this population is also helium-depleted, with spectra dominated by highly ionized emission lines of carbon and oxygen (types WC/WO). Evidence indicates that the most commonly observed supernova explosions that lack hydrogen and helium (types Ib/Ic) cannot result from massive WC/WO stars2,3, leading some to suggest that most such stars collapse directly into black holes without a visible supernova explosion4. Here we report observations of SN 2019hgp, beginning about a day after the explosion. Its short rise time and rapid decline place it among an emerging population of rapidly evolving transients5-8. Spectroscopy reveals a rich set of emission lines indicating that the explosion occurred within a nebula composed of carbon, oxygen and neon. Narrow absorption features show that this material is expanding at high velocities (greater than 1,500 kilometres per second), requiring a compact progenitor. Our observations are consistent with an explosion of a massive WC/WO star, and suggest that massive Wolf-Rayet stars may be the progenitors of some rapidly evolving transients.
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OBJECTIVE: To compare the neonatal and maternal outcomes as well as the mode of delivery of intended vaginal breech deliveries in women with a prior cesarean section to primiparous patients. STUDY DESIGN: The prospective monocenter cohort study was conducted among 604 women who presented for an intended vaginal singleton breech delivery at term between January 2007 and December 2016. RESULTS: Out of 37 women with a prior cesarean 19 had a successful vaginal delivery. 344 of 567 primiparous women had a successful vaginal delivery. Neonatal morbidity and mortality as well as maternal outcome were not significantly different in successful vaginal deliveries of women with prior cesarean compared to primiparous patients. The cesarean section rate was not significantly higher in the group of women with a prior cesarean (49%) compared to the group of primipara (39%). CONCLUSION: A prior cesarean should not be taken as an exclusion criterion for a planned vaginal delivery out of a breech presentation at term. Large multicenter, case-controlled studies are necessary to implement international guidelines.
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Apresentação Pélvica , Cesárea , Apresentação Pélvica/cirurgia , Estudos de Coortes , Parto Obstétrico , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Estudos ProspectivosRESUMO
Long γ-ray bursts are associated with energetic, broad-lined, stripped-envelope supernovae1,2 and as such mark the death of massive stars. The scarcity of such events nearby and the brightness of the γ-ray burst afterglow, which dominates the emission in the first few days after the burst, have so far prevented the study of the very early evolution of supernovae associated with γ-ray bursts3. In hydrogen-stripped supernovae that are not associated with γ-ray bursts, an excess of high-velocity (roughly 30,000 kilometres per second) material has been interpreted as a signature of a choked jet, which did not emerge from the progenitor star and instead deposited all of its energy in a thermal cocoon4. Here we report multi-epoch spectroscopic observations of the supernova SN 2017iuk, which is associated with the γ-ray burst GRB 171205A. Our spectra display features at extremely high expansion velocities (around 115,000 kilometres per second) within the first day after the burst5,6. Using spectral synthesis models developed for SN 2017iuk, we show that these features are characterized by chemical abundances that differ from those observed in the ejecta of SN 2017iuk at later times. We further show that the high-velocity features originate from the mildly relativistic hot cocoon that is generated by an ultra-relativistic jet within the γ-ray burst expanding and decelerating into the medium that surrounds the progenitor star7,8. This cocoon rapidly becomes transparent9 and is outshone by the supernova emission, which starts to dominate the emission three days after the burst.
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La localización del osteocondroma en la tibia distal es poco frecuente y su crecimiento con compromiso y deformidad del peroné distal es aún más raro, haciéndolo una condición más sintomática que en otras ubicaciones. Factores como la severidad de los síntomas, deformidad progresiva del tobillo, complicaciones sindesmóticas, riesgo de fractura patológica o transformación maligna, junto con nuevas y mejores técnicas quirúrgicas, han llevado a que el manejo expectante de esas lesiones sea excepcional y escasamente reportado. Presentamos el caso de un joven de 17 años con osteocondroma solitario interóseo tibio distal sintomático y compromiso fibular, que fue exitosamente manejado en forma expectante. A los 5 años de seguimiento clínico-radiológico no presenta complicaciones y la lesión se mantiene estable.
Osteochondromas located in the distal tibia are a rare condition, and the involvement of the distal fibula with deformity is even more uncommon. Factors such as the severity of symptoms, progressive deformity of the ankle, syndesmotic complications, the risk of pathological fracture or malignant transformation, together with new and safer surgical techniques, have led to scarce reports of non-surgical management. We present a case report of a 17-year-old male with a symptomatic interosseous solitary osteochondroma in the distal tibia with fibular involvement, which was successfully managed non surgically. After 5 years of clinical and radiological follow-up, he has no complications, and the lesion remains stable.
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Humanos , Masculino , Adolescente , Tíbia , Neoplasias Ósseas/terapia , Osteocondroma/terapiaRESUMO
Motivation: In the new release of pymzML (v2.0), we have optimized the speed of this established tool for mass spectrometry data analysis to adapt to increasing amounts of data in mass spectrometry. Thus, we integrated faster libraries for numerical calculations, improved data retrieving algorithms and have optimized the source code. Importantly, to adapt to rapidly growing file sizes, we developed a generalizable compression scheme for very fast random access and applied this concept to mzML files to retrieve spectral data. Results: pymzML performs at par with established C programs when it comes to processing times. However, it offers the versatility of a scripting language, while adding unprecedented fast random access to compressed files. Additionally, we designed our compression scheme in such a general way that it can be applied to any field where fast random access to large data blocks in compressed files is desired. Availability and implementation: pymzML is freely available on https://github.com/pymzML/pymzML under GPL license. pymzML requires Python3.4+ and optionally numpy. Documentation available on http://pymzml.readthedocs.io.
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Compressão de Dados/métodos , Espectrometria de Massas/métodos , Software , Algoritmos , Proteômica/métodosRESUMO
The introduction of colloidal single-layer carbon nitride (SLCN) nanosheets at the stage of the formation of Au nanocrystals (NCs) in aqueous solutions allows the surface plasmon resonance peak position of gold/SLCN composites to be tuned in a relatively broad range of 520-610 nm. The effect is believed to originate from a strong electronic interaction between Au NCs and SLCN nanosheets attached to their surface as capping ligands and resulting in a decrease of the effective electron density on the Au NC surface. The SLCN nanosheets suppress direct interparticle interactions between Au NCs prohibiting additional plasmonic features typical for the Au NC associates. Species similar to SLCN in terms of functionalities but having no conjugated aromatic system, such as polyethyleneimine, only induce aggregation of Au NCs but do not allow the main surface plasmon resonance of the NCs to be tuned demonstrating the crucial role of electronic interaction between the NC surface and the aromatic SLCN sheets for the surface plasmon resonance tuning.
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A subset of patients with depression have elevated levels of inflammatory cytokines, and some studies demonstrate interaction between inflammatory factors and treatment outcome. However, most studies focus on only a narrow subset of factors in a patient sample. In the current study, we analyzed broad immune profiles in blood from patients with treatment-resistant depression (TRD) at baseline and following treatment with the glutamate modulator ketamine. Serum was analyzed from 26 healthy control and 33 actively depressed TRD patients free of antidepressant medication, and matched for age, sex and body mass index. All subjects provided baseline blood samples, and TRD subjects had additional blood draw at 4 and 24 h following intravenous infusion of ketamine (0.5 mg kg-1). Samples underwent multiplex analysis of 41 cytokines, chemokines and growth factors using quantitative immunoassay technology. Our a priori hypothesis was that TRD patients would show elevations in canonical pro-inflammatory cytokines; analyses demonstrated significant elevation of the pro-inflammatory cytokine interleukin-6. Further exploratory analyses revealed significant regulation of four additional soluble factors in patients with TRD. Several cytokines showed transient changes in level after ketamine, but none correlated with treatment response. Low pretreatment levels of fibroblast growth factor 2 were associated with ketamine treatment response. In sum, we found that patients with TRD demonstrate a unique pattern of increased inflammatory mediators, chemokines and colony-stimulating factors, providing support for the immune hypothesis of TRD. These patterns suggest novel treatment targets for the subset of patients with TRD who evidence dysregulated immune functioning.
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Citocinas/imunologia , Transtorno Depressivo Maior/imunologia , Transtorno Depressivo Resistente a Tratamento/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Adulto , Estudos de Casos e Controles , Quimiocinas/imunologia , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Feminino , Fator 2 de Crescimento de Fibroblastos/imunologia , Humanos , Inflamação , Infusões Intravenosas , Interleucina-1alfa/imunologia , Interleucina-1beta/imunologia , Interleucina-6/imunologia , Ketamina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento , Fator de Necrose Tumoral alfa/imunologiaRESUMO
The ReLEx® technique allows correction of refractive errors through the creation and extraction of refractive stromal lenticules. Contrary to excimer laser corneal refractive procedures, where the stromal tissue is photoablated, the extracted lenticules obtained with ReLEx® can be preserved. Recent studies and case reports have described autologous re-implantation and allogeneic implantation of refractive lenticules into femtosecond-laser created stromal pockets in order to reverse the refractive outcome of a myopic corneal refractive procedure, correct hyperopia, aphakia, presbyopia and treat keratoconus. The use of stromal lenticules has also been described for therapeutic purposes, with an allogenic lenticule being transplanted under a LASIK flap in order to restore corneal volume and reduce the refractive error in a case of excessive stromal tissue removal after LASIK. This review summarises the results of the latest case reports and studies that describe the implantation of cryopreserved or fresh refractive stromal lenticules and discusses the feasibility, safety and refractive outcomes of the procedure, on the basis of published literature as well as our own experience.
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Cirurgia da Córnea a Laser/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Erros de Refração/diagnóstico , Erros de Refração/terapia , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Resultado do Tratamento , Acuidade VisualRESUMO
Background The aim of this clinical trial was to check the results of laser built-in settings 3 years after ReLEx SMILE for moderate and high myopia in unselected "real life" patients. Patients and Methods 50 myopic eyes of 27 patients were called in for examination after 3 years. 25 of these eyes with a preoperative myopia under - 6D comprised the "moderate myopia subgroup". All surgeries were performed with the 500 kHz VisuMax® femtosecond laser (Carl Zeiss Meditec AG, Jena) in the "fast mode" setting. Results The spherical equivalent (SE) of the entire group changed from - 6.18 D (± 1.91) prior to surgery to - 0.18 D (± 0.39) 3 years later. The preoperative SE in the moderate myopia subgroup changed from - 4.71 D (± 0.94) to - 0.04 D (± 0.23). 14â% of 50 eyes gained one line and 22â% lost one line of CDVA. The regression between month 3 and 36 was 0.07D for the entire group and 0.06 D for the moderate myopia subgroup. There were no late side effects. Primary undercorrection was predominantly seen in eyes over - 6 D. Conclusion ReLEx SMILE shows remarkable stability over the entire range of myopias after 3 years, however primary undercorrection occurs predominantly in eyes of - 6.0 D, which necessitates nomogram adjustment.
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Cirurgia da Córnea a Laser/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Miopia/diagnóstico , Miopia/cirurgia , Acuidade Visual , Adulto , Cirurgia da Córnea a Laser/efeitos adversos , Medicina Baseada em Evidências , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Prevalência , Resultado do Tratamento , Adulto JovemRESUMO
INTRODUCTION: Field design changed substantially from extended-field RT (EF-RT) to involved-field RT (IF-RT) and now to involved-node RT (IN-RT) and involved-site RT (IS-RT) as well as treatment techniques in radiotherapy (RT) of Hodgkin's lymphoma (HL). The purpose of this article is to demonstrate the establishment of a quality assurance program (QAP) including modern RT techniques and field designs within the German Hodgkin Study Group (GHSG). METHODS: In the era of modern conformal RT, this QAP had to be fundamentally adapted and a new evaluation process has been intensively discussed by the radiotherapeutic expert panel of the GHSG. RESULTS: The expert panel developed guidelines and criteria to analyse "modern" field designs and treatment techniques. This work is based on a dataset of 11 patients treated within the sixth study generation (HD16-17). CONCLUSION: To develop a QAP of "modern RT", the expert panel defined criteria for analysing current RT procedures. The consensus of a modified QAP in ongoing and future trials is presented. With this schedule, the QAP of the GHSG could serve as a model for other study groups.
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Fidelidade a Diretrizes/estatística & dados numéricos , Doença de Hodgkin/epidemiologia , Doença de Hodgkin/radioterapia , Guias de Prática Clínica como Assunto , Garantia da Qualidade dos Cuidados de Saúde/estatística & dados numéricos , Radioterapia (Especialidade)/normas , Radioterapia Conformacional/normas , Alemanha/epidemiologia , Fidelidade a Diretrizes/normas , Humanos , Prevalência , Radioterapia Conformacional/estatística & dados numéricos , Fatores de Risco , Integração de Sistemas , Resultado do TratamentoRESUMO
Good quality, complementary-metal-oxide-semiconductor (CMOS) technology compatible, 200 mm graphene was obtained on Ge(001)/Si(001) wafers in this work. Chemical vapor depositions were carried out at the deposition temperatures of 885 °C using CH4 as carbon source on epitaxial Ge(100) layers, which were grown on Si(100), prior to the graphene synthesis. Graphene layer with the 2D/G ratio â¼3 and low D mode (i.e., low concentration of defects) was measured over the entire 200 mm wafer by Raman spectroscopy. A typical full-width-at-half-maximum value of 39 cm-1 was extracted for the 2D mode, further indicating that graphene of good structural quality was produced. The study also revealed that the lack of interfacial oxide correlates with superior properties of graphene. In order to evaluate electrical properties of graphene, its 2 × 2 cm2 pieces were transferred onto SiO2/Si substrates from Ge/Si wafers. The extracted sheet resistance and mobility values of transferred graphene layers were â¼1500 ± 100 Ω/sq and µ ≈ 400 ± 20 cm2/V s, respectively. The transferred graphene was free of metallic contaminations or mechanical damage. On the basis of results of DFT calculations, we attribute the high structural quality of graphene grown by CVD on Ge to hydrogen-induced reduction of nucleation probability, explain the appearance of graphene-induced facets on Ge(001) as a kinetic effect caused by surface step pinning at linear graphene nuclei, and clarify the orientation of graphene domains on Ge(001) as resulting from good lattice matching between Ge(001) and graphene nucleated on such nuclei.
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BACKGROUND: Injuries of the knee and ankle joint are a serious ongoing problem in soccer. Although there is a variety of prevention programmes, a significant reduction of severe knee injuries has not been observed. Therefore, current strategies for diagnostics and training need to be re-evaluated. OBJECTIVE: Our study aimed to test a totally new intervention strategy (fast response training on the SpeedCourt). The efficiency of this method was evaluated with youth soccer athletes. MATERIALS AND METHODS: 24 young male class A athletes (mean age 18.0â±â0.7 years) of a local soccer team underwent SpeedCourt training for 7 weeks (1 training session per weekâ=âTS) during the regular season of competition. TS contained life-kinetic elements (time of exercise: 15â-â30 seconds, break: 2 minutes) and included a warm-up phase (15 minutes) and fast response training on the SpeedCourt (30 minutes). The players were tested on the SpeedCourt with different tests (Counter Movement Jump (CMJ), shuttle run, tapping, 10-second sprint) before and after the training programme. RESULTS: The univariate single-factor analysis of variance showed significant improvements in all test parameters (η(2)>â0.10). The range varied between η(2)â=â0.106 (time of ground contact right leg) und η(2)â=â0.730 (reaction time right leg). We did not find any relevant correlations between the tests and parameters. The number of injury-related accidents involving the lower extremities was reduced by about 50â% during defined periods of time. CONCLUSION: Our data revealed that training with fast responses at the SpeedCourt system clearly improved speed and speed strength performance of young soccer athletes, which is remarkable given the low intensity of influences (one TS per week). The increase in performance was accompanied by a significant reduction of the injury rate.
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Traumatismos em Atletas/prevenção & controle , Desempenho Atlético/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Traumatismos do Joelho/prevenção & controle , Futebol/lesões , Futebol/fisiologia , Adolescente , Traumatismos em Atletas/fisiopatologia , Humanos , Traumatismos do Joelho/fisiopatologia , Masculino , Resultado do TratamentoRESUMO
Chip-based microfluidics enable the seamless integration of different functions into single devices. Here, we present microfluidic chips containing porous polymer monolithic columns as a means to facilitate chemical transformations as well as both downstream chromatographic separation and mass spectrometric analysis. Rapid liquid phase lithography prototyping creates the multifunctional device economically.
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The ability of the spinal cord to recover after partial or complete transection, and even reinitiate motor function, was investigated in several studies in cats. It has been shown that even after a complete spinalisation at the level of T12/T13, the possibility of restoration of hind-limb function is good. Central pattern generators (CPGs), located in the spinal cord, play an important role in this situation. Although CPGs alone are unable to restore function, the combination of CPGs with targeted and consistent mobility training and, in some cases, hind-limb sensory stimulation is essential to improve function. These result in a reorganisation of the CPGs and neuronal networks in the spinal cord. The age of the animal at the time of injury and the extent and localisation of lesions, play a crucial role in recovery. A new focus of research is the influence of neurotransmitters/neuromodulators on spinal-cord regeneration. How and to what extent these factors support locomotor training remains for further clinical investigation.
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Doenças do Gato/fisiopatologia , Doenças do Gato/terapia , Geradores de Padrão Central/citologia , Geradores de Padrão Central/fisiologia , Doenças da Medula Espinal/veterinária , Medula Espinal/citologia , Medula Espinal/fisiologia , Animais , Doenças do Gato/patologia , Gatos , Doenças da Medula Espinal/patologia , Doenças da Medula Espinal/reabilitaçãoRESUMO
Purpose. To evaluate whether prophylactic circumferential retinal cryopexy (CRC) can prevent pseudophakic retinal detachment (PRD) development after posterior capsule rupture (PCR) during phacoemulsification. Methods. Retrospective patient chart analysis of eyes experiencing a PCR during phacoemulsification. Comparison of PRD development between eyes receiving CRC (cryo+ group) or not (cryo- group). Results. Overall 106 patients were analyzed, thereof 61 (58%) in the cryo+ and 45 (42%) in the cryo- group. In both clusters a total of 10 PRDs (9.4%) occurred, thereof 3 (30%) in the cryo+ as well as 7 (70%) in the cryo- group (p = 0.087), 79.8 ± 81.58 weeks after PCR. Relative/absolute risk reduction in CRC-treated eyes was calculated to be 68%/11%. Prophylactic CRC reduced PRD development 0.3-fold. Number needed to treat was estimated to be 9.4. Conclusion. Prophylactic CRC might be a useful treatment option in eyes with PCR to hamper PRD development in the further course. Further research is indicated to evaluate this beneficial effect between eyes with and without a rupture of the anterior vitreous cortex and accompanying vitreous loss in an expanding number of eyes.
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BACKGROUND: Overview of the retropupillary implantation of iris claw intraocular lenses (Artisan®,Ophtec, Groningen, Niederlande and Verisyse(TM),AMO, Santa Ana CA). MATERIAL AND METHODS: A literature search and review of implantation techniques, patient selection, potential complications and management strategies. RESULTS: This approach has the advantage of a simple implantation technique, an anatomically correct implantation site (as compared to endocapsular implantation) and a relatively low complication rate. An intact iris is, however, a prerequisite for this technique. Ischemic vitreoretinopathies, such as diabetes or vascular occlusive entities, as well as uveitis might be considered as contraindications. CONCLUSIONS: The retropupillary implantation of iris claw intraocular lenses is an interesting and especially time-effective rehabilitation technique for aphakia.
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Câmara Anterior/cirurgia , Afacia Pós-Catarata/cirurgia , Iris/cirurgia , Implante de Lente Intraocular/instrumentação , Implante de Lente Intraocular/métodos , Lentes Intraoculares , Âncoras de Sutura , Humanos , Desenho de Prótese , Reoperação/instrumentação , Reoperação/métodosRESUMO
BACKGROUND: The four fundamental techniques of secondary intraocular lens (IOL) fixation, namely sulcus placement, scleral or iris suture fixation and scleral haptic fixation can be combined in special situations. AIM: When is a combination of different techniques advisable? METHODS: This article describes our experiences and gives an example of combined technique use. RESULTS: These situations arise in cases when neighboring ocular structures are only partially preserved or show particular distinctive defects that can be repaired at the time of secondary IOL anchoring. This article presents a case of IOL-induced iris chafing and traumatic iridodialysis which was closed by a combined technique of iris suture and scleral suture fixation. CONCLUSION: A combination of different anchoring techniques for secondary IOL implantation can achieve a simultaneous repair of perilenticular structures and reduce the amount of suture material used.
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Iris/lesões , Iris/cirurgia , Implante de Lente Intraocular/instrumentação , Implante de Lente Intraocular/métodos , Âncoras de Sutura , Técnicas de Sutura/instrumentação , Terapia Combinada/instrumentação , Terapia Combinada/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação/instrumentação , Reoperação/métodos , Resultado do TratamentoRESUMO
Nasal surgeries constitute an extensive manipulation of the nasal mucosa and therefore of structures related to trigeminal and olfactory sensitivity. While olfactory changes due to nasal surgery are relatively well investigated, there are only very few studies regarding trigeminal sensitivity. Aim of the present study was to investigate sensory changes after nasal surgery with special regard to the trigeminal sensitivity. In 38 patients prior to and around 12 weeks after nasal surgery the following psychophysical measures were performed: odor identification, odor discrimination, phenyl ethyl alcohol odor threshold, sensitivity to trigeminal stimuli, trigeminal detection thresholds and trigeminal pain thresholds. These results were compared to those of a control group (43 healthy volunteers). Psychophysical olfactory and trigeminal testing showed no major changes in patients after surgery compared to the control group. Independent from the time of measurement higher trigeminal detection thresholds were found in patients compared to healthy subjects, meaning that trigeminal thresholds were already increased before surgery. The present study revealed a decreased trigeminal sensitivity in patients already before surgery. It may be hypothesized that patients also exhibit a decreased sensitivity for nasal airflow, which may also contribute to the patients' impression of impaired nasal breathing.