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AIM: To compare the clinical efficacy, vault, and rotational stability of horizontal, oblique, and vertical implantation of Toric implantable collamer lens(TICL).METHODS: Retrospective cohort study. A total of 92 cases(120 eyes)who underwent TICL implantation from July 2018 to March 2022 and had regular follow-up for at least 1 a postoperatively(1 d, 1 wk, 1, 3, 6 mo, and 1 a)at Wuhan Bright Eye Hospital were collected. The patients were divided into three groups, with 34 cases(45 eyes)in horizontal implantation group, 25 cases(29 eyes)in oblique implantation group(29 cases), and 33 cases(46 eyes)in vertical implantation group. Uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), diopters, vault, and rotation angle(deviation of the actual axis of TICL from the expected axis).RESULTS: All surgeries were uneventful, and there were no complications such as infection, secondary glaucoma, or cataract opacity. Safety and efficacy of the surgery: the CDVA of the three groups of patients was better than or equal to the preoperative CDVA at 1 a postoperatively, and there was no statistically significant differences in postoperative UDVA and CDVA of the three groups(P>0.05). The safety index at 1a postoperatively was 1.34±0.21, 1.34±0.17, and 1.31±0.18 for the horizontal, oblique, and vertical groups, respectively. The efficacy index was 1.26±0.21, 1.33±0.18, and 1.27±0.16 for the three groups, respectively, both with no statistically significant differences(P>0.05). Vault: there was a significant difference in postoperative vault among the three groups(P=0.003), with the vertical group having the lowest vault, followed by the horizontal group and the oblique group. The vaults at different follow-up time points within each group showed significant differences(P<0.001), and all decreased over time. Residual astigmatism: there was no significant difference in residual astigmatism among the three groups(P=0.130), but there were differences at different follow-up time points within each group(P<0.001). Rotation angle: no significant differences in rotation angle were observed among the three groups(P=0.135), but there were differences at different follow-up time points within each group(P<0.001).CONCLUSION: The implantation of TICL in different orientations has good safety and efficacy, the postoperative rotational stability is good, and the appropriate angle can be selected to implant TICL according to the clinical situation.
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We report the outcomes of a custom-designed toric piggyback intraocular lens in a patient with high postoperative residual astigmatism. A 60-year-old male patient underwent customized toric piggyback IOL for postoperative residual astigmatism of 13 D, with follow-up examinations for IOL stability and refractive outcomes. The refractive error stabilized at two months and remained stable at one year, with a correction of nearly 9 D of astigmatism. The IOP remained within normal limits, and there were no postoperative complications. The IOL remained stable in the horizontal position. To our knowledge, this is the first case report of correction of unusually high astigmatism by a novel smart toric design of piggyback IOL.
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Traumatic brain injury ( TBI ) has caused serious economic and social burdens, but due to its heterogeneity, there is no effective treatment. In TBI with different severity, diffuse axonal injury (DAI) incidenceis high. The investigation on DAI will contribute to the diagnosis and treatment of TBI. In this study, the classification of TBI and the research status of DAI were summarized. The method to judge the severity of TBI and DAI, and animal experimental models and related injury criteria and thresholds were reviewed. The result show that DAI is mainly generated by rotational acceleration and it is related to angular acceleration, angular velocity and duration. Several TBI animal models can induce the pathology of DAI, and inertial rotation models which can produce only rotational acceleration have been developed. However, these models are instantaneous rotation models, and the rotation duration is uncontrollable, thus a longer duration is impossible, and DAI severity under long rotational motion cannot be studied. The study proposes that a new rotation animal model which can control rotation duration should be developed. The development of the animal model and investigation on pathomechanism of the model will contribute to the prevention and treatment of DAI.
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Objective:To evaluate the effect of rotational errors (antero-posterior) on dosimetric parameters of positive lymph nodes in the long target volumetric modulated arc therapy (VMAT) plan for advanced cervical cancer and investigate its coping strategies.Methods:Clinical data of patients with cervical cancer complicated with para-aortic or inguinal lymph node metastasis admitted to Affiliated Hospital of North Sichuan Medical College were randomly selected and retrospectively analyzed. The target areas of the lymph nodes at different distances from the center of the plan were outlined according to the requirements. After designing the VMAT plan on the CT images of each case, the rotational errors (antero-posterior) were introduced by changing the parameters of the treatment couch, and the dose distribution was reconstructed by dose calculation with other parameters unchanged. Then, the external boundary of the original lymph node target was added according to d=2πr(α/360) ( r is the distance from the center of the lymph node to the plan center), re-planned, and the changes of dosimetric parameters in the target area of the original lymph node were analyzed after the corresponding rotational errors were introduced. Results:When the distance between the lymph node target area and the plan center was 6 cm with an error of 3°, the distance was 9 cm and 12 cm with an error of 2.5°, the distance was 15 cm with an error of 2°, and the distance was 18 cm with an error of 1.5°, the mean change of D 95% was more than 5%. When the rotational errors were ≤1°, the mean change of D 95% in lymph node target area was less than 5%, and when the lymph node was 18 cm away from the treatment plan center, the mean change was more than 3%, reaching 3.75%. When the rotational errors were 0.5° and the distance from the plan center was 18 cm (0.5°, 18 cm), the dose change of lymph node target was more than 5%, reaching 5.58%. At (1°, 15 cm), the V 100% change reached 8.96%, and at (1°, 18 cm), the V 100% change was 14.5%. The D 95% and V 100% parameters of the original lymph node target were changed by less than 1% after adding the external boundary of the original lymph node target and introducing corresponding rotational errors. Conclusions:In the long target area radiotherapy of cervical cancer, the variation of dosimetric parameters of lymph node target was increased with the increase of rotational errors and with the increase of distance from the plan center. It is recommended to increase the efferent boundary of lymph nodes in different positions to avoid underdose by d=2πr(α/360).
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Objective:To compare the cost-effectiveness between open surgery and minimally invasive rotational surgery in patients with benign breast tumor, and to provide a theoretical support for the choice of surgical approach.Methods:The clinical data of 1 389 benign breast tumor patients underwent surgery from January 2017 to January 2020 in Beijing Friendship Hospital, Capital Medical University were retrospectively analyzed. Among them, 374 patients were treated with open surgery (open group), and 1 015 patients were treated with minimally invasive rotational surgery (minimally invasive group). The surgery-related and cost-effectiveness analysis indexes were compared between two groups.Results:The operation time, incidence of hematoma/subcutaneous bruising and cosmetic result satisfactory rate in minimally invasive group were significantly higher than those in open group: (37.37 ± 6.66) min vs. (34.58 ± 8.95) min, 10.54% (107/1 015) vs. 5.35% (20/374) and 98.72% (1 002/1 015) vs. 95.99% (359/374); while the incision length, length of hospital stay and pain score were significantly less than those in open group: (5.00 ± 0.00) mm vs. (26.55 ± 4.73) mm, (1.03 ± 0.36) d vs. (2.85 ± 1.99) d, (1.76 ± 1.56) scores vs. (2.72 ± 1.27) scores, and there were statistical differences ( P<0.01). The patients were followed up until May 2022. There were no incision infection, recurrence and residual lesions in the two groups. The total cost and cost-effectiveness ratio in minimally invasive group were significantly lower than those in open group: (6 553 ± 1 150) yuan vs. (7 965 ± 3 323) yuan and 71.10 ± 13.61 vs. 88.96 ± 37.48, the benefit score was significantly higher than that in open group: (96.50 ± 3.89) scores vs. (88.92 ± 6.39) scores, and there were statistical differences ( P<0.01). Conclusions:Compared with open surgery, minimally invasive rotational surgery is less costly and more benefits, so minimally invasive surgery should be the preferred surgical procedure for benign breast tumor.
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RESUMO Objetivo Avaliar a precisão da tomografia corneana com imagens de Scheimpflug (Pentacam® AXL, OCULUS, Wetzlar, Alemanha) nos padrões de escaneamento com 25 e 50 imagens, verificando sua repetibilidade e reprodutibilidade em olhos normais, com ceratocone e com ceratocone após crosslinking. Métodos Estudo prospectivo, transversal, misto, no qual foram incluídos os pacientes que tinham córneas normais, ou com ceratocone; e não tinham realizado cirurgias corneanas, com exceção do crosslinking. Foram excluídos os pacientes que tivessem realizado outras cirurgias, como implante de anel intracorneano ou transplante de córnea. Foram realizadas três medidas com 25 imagens e três medidas com 50 imagens em cada olho incluído no estudo. Resultados O estudo avaliou 54 olhos de 41 pacientes. Destes, dez (18,52%) olhos eram com córneas normais e sem cirurgia ocular prévia aleatoriamente selecionados de 5 pacientes; 22 (40,74%) olhos aleatoriamente selecionados de 18 pacientes com ceratocone, sem cirurgia ocular prévia; e 22 (40,74%) olhos com ceratocone de 18 pacientes operados por crosslinking. No estudo da repetibilidade, percebemos uma maior variação de valores em todos os índices nos pacientes com ceratocone comparados aos de pacientes com olhos normais, em grande parte dos parâmetros analisados. Conclusão Não houve diferença significativa entre os métodos de escaneamento por 25 e 50 imagens, sendo o escaneamento por 25 imagens mais conveniente. A presença de ceratocone teve impacto negativo na repetibilidade de ambos os tipos de exame, e foi grande a concordância entre os métodos nos três grupos estudados. O coeficiente de repetibilidade permite considerar a relevância clínica dos dados para avaliar a progressão de ceratocone.
ABSTRACT Objective To evaluate the accuracy of corneal tomography with Scheimpflug images (Pentacam® AXL, OCULUS, Wetzlar, Germany) in scanning patterns with 25 and 50 images, by analyzing their repeatability and reproducibility in normal eyes, eyes with keratoconus and with keratoconus after crosslinking. Methods Prospective, cross-sectional, mixed study including patients who had normal corneas, or who had keratoconus, who had not undergone corneal surgery, with the exception of crosslinking. Patients who had undergone surgery for intracorneal ring implantation or corneal transplantation were excluded. Three measurements were performed with 25 images and three measurements were performed with 50 images on each eye included in the study. Results The study evaluated a total of 54 eyes of 41 patients. Of these, 10 (18.52%) eyes had normal corneas, without previous eye surgery, 22 (40.74%) were eyes with keratoconus, without previous eye surgery, and 22 (40.74%) were eyes with keratoconus, with crosslinking for keratoconus. In the study of repeatability, we noticed a greater variation of values in all indices in patients with KC compared to those with normal eyes, in most of the parameters analyzed. Conclusion There is no significant difference between the scanning methods with 25 and 50 images. However, 25 scans has advantages that make it the main method suggested. The presence of keratoconus has a negative impact on the repeatability of both types of examination, and there is great agreement between the methods in the three groups studied. The high repeatability coefficient in some parameters suggests that these data should be used with care in the assessment of keratoconus progression.
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The purpose of this study is to compare short term outcome of rotablation in ACS versus non-ACS patients. 60 Consecutive patients who underwent rotational atherectomy were followed prospectively. The mean duration of follow up was 13.05 ± 5.2 months. The mean ejection fraction was 52.41% ± 9.4%. 45% patients had diagnosis of CSA and 55% were ACS. The mean syntax score was 29.23 ± 7.99. LAD was the most common vessel treated by RA in 76.6%. Rotablation of LM was done in 30%. IVUS guided procedure was done in 66.7%. RA can be done with comparable safety and success in both non-ACS and ACS patients
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Student doctor method of clinical training or clinical clerkship provides students with exposure to the entire longitudinal illness of the patient. The students participate in patient care as a part of treating team and can refine their clinical, communication and procedural skills. It provides them with an opportunity to work with the faculty and experience the future workplace. Although the graduate medical education regulations (GMER) provide for student doctor method of training, the time provided is too little and opportunistic. Electives have also been recently added to the new curriculum for the first time. We propose a model to deliver the electives using the clerkship method, so as to consolidate what students learn from the ongoing clerkship. This model is feasible, practical and can be introduced in the current GMER for Indian medical undergraduates without any major disruptions.
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Resumen: La tromboelastometría evalúa los cambios viscoelásticos en el proceso de coagulación. Nos ofrece una representación gráfica de la formación del coágulo, la estabilidad del mismo y la presencia de lisis. La tromboelastometría rotacional es una herramienta diagnóstica que representa de forma gráfica la funcionalidad del coágulo para un manejo dirigido e individualizado de la coagulopatía asociada a hemorragia. En este trabajo se puntualiza cómo la tromboelastometría rotacional es a la coagulación como el electrocardiograma es al corazón.
Abstract: Thromboelastometry evaluates viscoelastic changes in the coagulation process. It offers us a graphic representation of the formation of the clot, its stability and the presence of lysis. Rotational thromboelastometry is a diagnostic tool that graphs the functionality of the clot, for a targeted and individualized management of bleeding-associated coagulopathy. In this work it is specified how rotational thromboelastometry is to coagulation as the electrocardiogram is to the heart.
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Bleeding during cardiac surgery, liver transplant, trauma and post partum hemorrhage are often multifactorial and these factors are dynamic as new factors crop up during the course of management. Conventional tests of coagulation offer information of a part of the coagulation system and also is time consuming. Viscoelastic point of care tests (VE POCTs) like rotational thromboelastometry, thromboelastogram and Sonoclot, are based on analysis of the viscoelastic properties of clotting blood and provide information for the entire coagulation pathway. In this comprehensive review being presented here, we have examined the pros and cons of VE POCTs including clinical, cost and survival benefits. The recommendations of the various guidelines regarding use of VE POCTs in various scenarios have been discussed. The review also tried to offer suggestions as to their optimal role in management of bleeding during cardiac surgeries, extracorporeal membrane oxygenation, left ventricular assist devices, liver transplant and briefly in trauma and postpartum hemorrhage.
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Correcting astigmatism safely and effectively has become a crucial part of modern cataract surgery due to the transformation of the surgery into a refractive procedure. The increased predictability and enhanced safety of Toric intraocular lens(IOL)implantation has made it the preferred method of correcting corneal regular astigmatism above 0.75D in cataract surgery. Toric IOL needs to be implanted in a precise axis position to achieve good astigmatism correction. A major cause of toric misalignment is postoperative rotation, which typically occurs soon after surgery. However, large axis misalignment will eliminate the astigmatism corrective effect of Toric IOL, even cause astigmatism in a new axis position. The factors responsible for IOL postoperative rotation are diverse. As a result, profound understanding of the factors is crucial for clinicians to minimize the rotation. Repositioning procedure is generally selected in case of significant rotation and the timing of the procedure is vital. This paper reviewed the influencing factors of IOL rotation postoperatively and its principle of treatment.
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Objective: To explore the feasibility of the single-stage stent implantation following rotational atherectomy combined with transcatheter aortic valve replacement (TAVR) in treating patients with severe aortic stenosis(AS) and severe calcified coronary artery stenosis. Methods: Three patients who received single-stage stent implantation following rotational atherectomy combined with TAVR in Fuwai hospital from April to October 2019 were included in this retrospective analysis. Clinical and anatomical features (including echocardiography and aortic CT) of the patients were collected, efficacy and safety of this operation strategy were observed and 6 months follow up results were summarized. Results: Three patients (2 females, 66-80 years old) were included. The mean Society of Thoracic Surgeons (STS) risk score was 7.8%. The mean maximum velocity of aortic valve was 4.4 m/s, the mean transvalvular pressure gradient was 53.2 mmHg (1 mmHg=0.133 kPa), mean left ventricular ejection fraction (LVEF) was 48.6%. All three patients had severe calcified coronary artery stenosis: left anterior descending artery (LAD, n=2) and left main coronary artery (LM, n=1), requiring rotary grinding. The mean SYNTAX score was 20. All the procedures were performed through transfemoral access. After aortic valve crossing, all coronary lesions were successfully treated with stent implantation following rotational atherectomy, transfemoral TAVR was then immediately performed with a self-expandable Venus-A valve. One patient underwent"valve-in-valve"implantation due to the high-implantation position of the first valve. The procedures were completed without complications in all the three patients. The immediate effect was satisfactory. Echocardiography results showed that the mean maximum velocity of aortic valve was 2.1 m/s, mean gradient was 9.3 mmHg, and mean LVEF was 59% after the procedure. There was no death and revascularization during the 6 months follow-up. Conclusion: In patients with severe calcified coronary artery and severe AS with high risk of cardiac surgery, the single-stage stent implantation following rotational atherectomy combined with TAVR is feasible and results are satisfactory in this patient cohort.
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Objective To compare rotational techniques used by Chinese and world elite men’s shot put athletes, so as to provide scientific references for Chinese male shot putters to improve their sports performance and results in international competitions. Methods Three-dimensional (3D) kinematics data from Chinese male shot putters in actual competitions were obtained, and kinematic parameters of Chinese and world elite men’s shot put athletes were calculated and compared. Namely, shot velocities and hip-shoulder separation angles at five critical instants of rotational techniques: right foot off, left foot off, right foot touchdown, left foot touchdown and release, as well as phase durations and shot travel distances during four critical phases: first single support, air-born flight, second single support and final delivery. ResultsCompared with world elite athletes, Chinese male shot putters using rotational techniques had significantly lower vertical release velocity, longer air-borne duration, smaller hip-shoulder separation angles at left foot off and touchdown instant, and longer shot travel distance during air-borne flight, but shorter shot travel distance during final shot delivery. Conclusions The difference in lower extremity strength is a primary casue leading to different sports performance between Chinese and world elite male shot putters. The technique differences in Chinese and world elite male shot putters mainly lie in different phase timing and shot travel distances during different techinique phases.
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@#AIM: To compare the clinical effects of two brands of Toric intraocular lens(IOL)used in surgical correction of cataract with corneal astigmatism.<p>METHODS: Totally 35 patients(50 eyes)with corneal astigmatism who underwent ophthalmic surgery from April 2019 to July 2019 were retrospectively analyzed. Among them, 25 eyes of 20 patients were implanted with Rayner 623T, while 25 eyes of 15 patients with Alcon AcrySof Toric IOL. Three months after surgery, the uncorrected distance visual acuity(UCDVA), best corrected distance visual acuity(BCDVA), residual astigmatism, rotational degree of intraocular lens, contrast sensitivity, objective visual quality and the National Eye Institute 25-Item Visual Function Questionnaire(NEI VFQ-25)scale score were compared. Vector analysis was performed using the Alpins method.<p>RESULTS: The mean postoperative UCDVA(LogMAR)and BCDVA(LogMAR)in the Rayner group were 0.17±0.20 and 0.08±0.15, respectively(<i>P</i>>0.05), while those in the Alcon group were 0.21±0.16 and 0.10±0.11, respectively(<i>P</i>>0.05). The mean residual astigmatism in the Rayner group was(-0.57±0.24)D while that in the Alcon group was(-0.50±0.28)D(<i>P</i>>0.05). There was no statistically significant difference between the two groups in IOL rotational stability, vector analysis parameters, contrast sensitivity and objective visual quality(<i>P</i>>0.05). The NEI VFQ-25 scale score was 85.16±5.91 in the Rayner group while it was 82.08±6.16 in the Alcon group(<i>P</i>>0.05).<p>CONCLUSION: The two brands of Toric IOL-Rayner 623T and Alcon AcrySof Toric showed no significant difference in their clinical outcomes.
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@#With the development of refractive cataract surgery,Toric intraocular lens(Toric IOL)has been widely used in the treatment of cataract patients with regular astigmatism. And the rotational stability of Toric IOL has been paid more and more attention. This article reviewed the evaluation method of the rotation stability, and analyzed various related influencing factors.
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The aim of this study was to evaluate the effect of grazing methods and intensities on the metabolic profile of lambs grazing ryegrass. This study was performed in Eldorado do Sul (RS). The treatments consisted of two grazing intensities with rotational and continuous stocking methods: moderate and low. The experimental design was a randomized block arranged in a factorial scheme with four replicates. To evaluate the metabolic and nutritional conditions of the lambs, blood samples were collected to evaluate phosphorus, albumin, glucose, magnesium, globulin, cortisol, urea and total proteins. The highest blood urea value was observed in the month of September in lambs kept in continuous method grazing. There was no statistical difference between the grazing intensities and grazing methods for albumin, glucose, magnesium, globulin, cortisol and total protein levels in profile lambs. The cortisol values suggested that the animals were not subjected to high stress levels. In conclusion, rearing female lambs on ryegrass, irrespective of grazing methods or intensities, allowed the maintenance of body homeostasis and did not cause any metabolic unbalances, nutritional unbalances or stress.(AU)
O objetivo deste estudo foi avaliar o efeito dos métodos e das intensidades de pastejo no perfil metabólico de cordeiros. Este estudo foi realizado em Eldorado do Sul (RS). Os tratamentos consistiram em duas intensidades de pastejo (moderada e baixa), com métodos lotação rotativa e lotação contínua. O delineamento experimental foi em blocos ao acaso, em esquema fatorial com quatro repetições. Para avaliar as condições metabólicas e nutricionais dos cordeiros, foram coletadas amostras de sangue para avaliar fósforo, albumina, glicose, magnésio, globulina, cortisol, ureia e proteínas totais. O maior valor de ureia no sangue foi observado no mês de setembro nos cordeiros mantidos em pastejo contínuo. Não houve diferença estatística entre as intensidades de pastejo e os métodos de pastejo para albumina, glicose, magnésio, globulina, cortisol e níveis de proteína total nos cordeiros perfilados. Os valores de cortisol sugeriram que os animais não foram submetidos a altos níveis de estresse. Concluindo, a criação de cordeiros em azevém, independentemente dos métodos ou das intensidades de pastejo, permitiu a manutenção da homeostase corporal e não causou desequilíbrios metabólicos, desequilíbrios nutricionais ou estresse.(AU)
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Animals , Female , Lolium , Animal Welfare , Sheep/metabolism , Sheep/blood , Pasture/analysis , Body Temperature RegulationABSTRACT
Introduction: The aim of the present study was to compare two immobilization systems for comparison of setup errors in targeted radiotherapy. Methods: Retrospective analysis was done for the patients undergoing radiotherapy from May 2012 to December 2018 at our institution. Immobilization was performed on 30 patients sessions (Vacuum cushion i.e., Vac-Lok™ = 15; Thermoplastic mould i.e., Pelvicast pelvic masks = 15). A total of 763 cone-beams were analysed. The target lesion location was verified by cone-beam computed tomography (CBCT) prior to each session, with displacements assessed by CBCT simulation prior to each treatment session. Systematic setup errors, random setup errors, isocenter deviations in the Medio-lateral (ML), Supero-inferior (SI), Antero-posterior (AP), Rotation (yaw) directions of the patient position was calculated. Results: On comparing the Vac-Lok™ and Pelvicast pelvic masks group with respect to Systematic and random error in the lateral, longitudinal, vertical and YAW direction, no statistically significant difference was seen except the random error in YAW direction (P=0.037, Unpaired t-test). There was no difference observed in comparing the isocentric deviation. Conclusion: It was inferred and concluded that using a vacuum cushion for pelvic radiotherapy provides no added benefit compared to using a thermoplastic mould. Thermoplastic mould is recommended for patients receiving pelvic radiotherapy to improve overall reproducibility
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Although belonging to the same species, different Brachiaria brizantha varieties used for pasture vary significantly in their morphological structure. Therefore, this study starts from the central hypothesis that the defoliation dynamics during the period of occupation by animals in pastures formed by Brachiaria brizantha under rotational stocking varies among cultivars during the year. The experimental design used was randomized blocks with three treatments and three repetitions, with the cultivars consisting of Brachiaria brizantha cv. Xaraés, BRS Paiaguás, and Ecótipo B4. The defoliation patterns during the grazing periods were estimated using the marked tiller technique. Despite alterations in the tiller and forage mass components in the wet and dry seasons, no variations were observed in the tiller defoliation dynamics and the respective structural components. In the wet season, the area grazed only once was greater for BRS Paiaguás compared to the other two cultivars, but the other areas representing the grazing horizons were equally exploited among the grass varieties during the year. Therefore, based on the defoliation dynamics of pastures in Brazil's tropical climate, it is possible to suggest that pastures formed by grasses with different structures and growth habits can be submitted to similar management strategies without impairing the forage canopy exploitation by the animals.
Apesar de pertencerem à mesma espécie, existem diversas variedades disponíveis no mercado de pastos de Brachiaria brizantha, os quais variam significativamente na estrutura. Assim, este trabalho partiu da hipótese central que a dinâmica de desfolhação durante o período de ocupação dos animais em pastos de Brachiaria brizantha, sob lotação rotativa, varia entre cultivares ao longo do ano. O delineamento experimental utilizado foi de blocos casualizados com três tratamentos e três repetições constituídos pelas Brachiaria brizantha cv. Xaraés, BRS Paiaguás e o ecótipo B4. Os padrões de desfolhação, durante o rebaixamento dos pastos, foram estimados utilizando a técnica de perfilhos marcados. Apesar de alterações nos componentes do perfilho e massa de forragem, na época das águas e secas, não foi observado variações na dinâmica de desfolhação de perfilho e seus respectivos componentes estruturais. No período das águas a área pastejada apenas uma vez, foi maior na BRS Paiaguás quando comparado aos demais pastos, porém as demais áreas que equivalem aos horizontes de pastejo foram igualmente exploradas entre as gramíneas durante o ano. Portanto, baseado na dinâmica de desfolhação em pastos de clima tropical, é possível sugerir que pastos formados com gramíneas com diferentes estruturas e hábitos de crescimento podem ser submetidos a semelhantes estratégias de manejo sem prejudicar o processo de exploração do dossel forrageiro pelo animal.