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1.
Sports (Basel) ; 12(5)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38787006

RESUMO

This study aimed to verify whether there are differences in the body composition, functionality, lower-limb power, agility, and cardiorespiratory capacity in futsal players, comparing futsal athletes by competitive level. The athletes (N = 84) were divided into three groups: group Elite (N = 29), group Sub-Elite (N = 29), and group Non-Elite (N = 26). Anthropometric variables were analyzed through a bioimpedance scale (Inbody 270), and functionality was analyzed through a functional movement screen battery. The power of the lower limbs was tested with the Abalakov jump, the agility with the zigzag agility test, and the cardiorespiratory capacity through the futsal intermittent endurance test. Anthropometric data from futsal athletes revealed a homogeneity in relation to the variables analyzed, regardless of the level of competition in which they operate. In performance variables, the power of the members and functionality was considered a discriminating factor of the level of competitiveness of the athletes, with the Elite group athletes presenting the best values. We concluded that there were no differences in relation to the body composition of the athletes. However, the athletes of higher levels, as a rule, present better performances in physiological aspects, results that can be explained by the fact that there is a better periodization in terms of training, with more intense loads and more complex competitive calendars, thus resulting in a greater specialization of these athletes.

2.
ACS Appl Mater Interfaces ; 16(7): 8655-8667, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38301168

RESUMO

Currently, magnetocaloric refrigeration technologies are emerging as ecofriendly and more energy-efficient alternatives to conventional expansion-compression systems. However, major challenges remain. A particular concern is the mechanical properties of magnetocaloric materials, namely, their fatigue under cycling and difficulty in processing and shaping. Nevertheless, in the past few years, using multistimuli thermodynamic cycles with multicaloric refrigerants has led to higher heat-pumping efficiencies. To address simultaneously the challenges and develop a multicaloric material, in this work, we have prepared magnetocaloric-based flexible composite mats composed of micrometric electroactive (EA) polyvinylidene fluoride (PVDF) fibers with embedded magnetocaloric/strictive La(Fe,Si)13 particles by the simple and cost-effective electrospinning technique. The composite's structural characterization, using X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, and measurements of the local-scale piezoresponse, revealed a cubic NaZn13-type structure of the La(Fe,Si)13 phase and the formation of the dominant polar ß-phase of the PVDF polymer. The PVDF-La(Fe,Si)13 composite showed an enhancement of the longitudinal piezoelectric coefficient (effective d33) (-11.01 pm/V) compared with the single PVDF fiber matrix (-9.36 pm/V). The main magnetic properties of La(Fe,Si)13 powder were retained in the PVDF-La(Fe,Si)13 composite, including its giant magnetocaloric effect. By retaining the unique magnetic properties of La(Fe,Si)13 embedded in the electroactive piezoelectric polymer fiber mats, we have designed a flexible, easily shapeable, and multifunctional composite enabling its potential application in multicaloric heat-pumping devices and other sensing and actuating devices.

3.
Sci Rep ; 13(1): 10858, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37407609

RESUMO

Response to fertilisation with biochar is greatest in field crops on acidic tropical soils, but limited information is available for vegetable crops. As a case-study using vegetable production in Timor-Leste, we assessed if biochar alleviates nutritional constraints to vegetables in low-nutrient soils. Field trials on vegetable crops were conducted with fertiliser combinations of rice husk biochar, phosphate and local fertiliser at three sites. A pot soil incubation trial of biochar was undertaken with soil from the acid site, where rice husk biochar had a larger effect on productivity than the other fertilisers in chili pepper, tomato and soybean with an average yield increase with biochar of 230% over control. Combining phosphate with biochar augmented the yield over biochar alone in chili pepper, tomato and soybean. At neutral and alkaline sites, fertilisation with biochar lifted mean yield over the control. Soil constraints alleviated by fertiliser were primarily from P and Zn deficiencies. Marked increases in vegetable yields, among the highest globally, were achieved with fertilisation with biochar individually and in combination with phosphate in low nutrient soil in Timor-Leste. Clearly, rice husk biochar is a promising avenue to fertilise the soil with P and Zn and increase crop productivity in Timor-Leste.


Assuntos
Oryza , Solo , Verduras , Fertilizantes , Timor-Leste , Carvão Vegetal , Produtos Agrícolas , Fosfatos , Nutrientes
4.
Cancers (Basel) ; 15(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36672333

RESUMO

Colorectal cancer is the third most common cancer worldwide. Despite recent advances in the treatment of this pathology, which include a personalized approach using radio- and chemotherapies in combination with advanced surgical techniques, it is imperative to enhance the performance of these treatments and decrease their detrimental side effects on patients' health. Nanomedicine is likely the pathway towards solving this challenge by enhancing both the therapeutic and diagnostic capabilities. In particular, plasmonic nanoparticles show remarkable potential due to their dual therapeutic functionalities as photothermal therapy agents and as radiosensitizers in radiotherapy. Their dual functionality, high biocompatibility, easy functionalization, and targeting capabilities make them potential agents for inducing efficient cancer cell death with minimal side effects. This review aims to identify the main challenges in the diagnosis and treatment of colorectal cancer. The heterogeneous nature of this cancer is also discussed from a single-cell point of view. The most relevant works in photo- and radiotherapy using nanotechnology-based therapies for colorectal cancer are addressed, ranging from in vitro studies (2D and 3D cell cultures) to in vivo studies and clinical trials. Although the results using nanoparticles as a photo- and radiosensitizers in photo- and radiotherapy are promising, preliminary studies showed that the possibility of combining both therapies must be explored to improve the treatment efficiency.

5.
Materials (Basel) ; 15(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36556665

RESUMO

Prussian Blue (PB) thin films were prepared by DC chronoamperometry (CHA), symmetric pulse, and non-symmetric pulse electrodeposition techniques. The formation of PB was confirmed by infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX) and UV-Vis transmission measurements. X-ray diffraction (XRD) shows the stabilization of the insoluble form of PB. From scanning electron microscopy (SEM) studies, an increase in porosity is obtained for the shorter pulse widths, which tends to improve the total charge exchange and electrochemical stability of the films. While the film prepared by CHA suffered a degradation of 82% after 260 cycles, the degradation reduced to 24% and 34% for the samples prepared by the symmetric and non-symmetric pulse methods, respectively. Additionally, in the non-symmetric pulse film, the improvement in the charge exchange reached ~522% after 260 cycles. According to this study, the deposition time distribution affects the physical/chemical properties of PB films. These results then render pulse electrodeposition methods especially suitable to produce high-quality thin films for electrochemical devices, based on PB.

6.
ACS Appl Mater Interfaces ; 14(38): 43498-43507, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36099579

RESUMO

Zero thermal expansion (ZTE) composites are typically designed by combining positive thermal expansion (PTE) with negative thermal expansion (NTE) materials acting as compensators and have many diverse applications, including in high-precision instrumentation and biomedical devices. La(Fe1-x,Six)13-based compounds display several remarkable properties, such as giant magnetocaloric effect and very large NTE at room temperature. Both are linked via strong magnetovolume coupling, which leads to sharp magnetic and volume changes occurring simultaneously across first-order phase transitions; the abrupt nature of these changes makes them unsuitable as thermal expansion compensators. To make these materials more useful practically, the mechanisms controlling the temperature over which this transition occurs and the magnitude of contraction need to be controlled. In this work, ball-milling was used to decrease particles and crystallite sizes and increase the strain in LaFe11.9Mn0.27Si1.29Hx alloys. Such size and strain tuning effectively broadened the temperature over which this transition occurs. The material's NTE operational temperature window was expanded, and its peak was suppressed by up to 85%. This work demonstrates that induced strain is the key mechanism controlling these materials' phase transitions. This allows the optimization of their thermal expansion toward room-temperature ZTE applications.

7.
Sci Rep ; 12(1): 9911, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701579

RESUMO

In the Iberian Peninsula the fossil record of artiodactyls spans over 53 million years. During the Pleistocene, wild cattle species such as Bison and especially Bos became common. In Late Pleistocene, the aurochs (Bos primigenius) was widespread and the only bovine living along the large river valleys of southern Iberia. Although commonly found in fossil sites and especially in cave bone assemblages, the trace fossil record of aurochs was known worldwide only from the Holocene. Large bovine and roe deer/caprine tracks were found in at least five horizons of the early Late Pleistocene (MIS 5) beach and eolian deposits of Cape Trafalgar (Cadiz Province, South of Spain). The large bovine tracks are formally described as Bovinichnus uripeda igen. et isp. nov. and compared with the record of aurochs tracks, large red deer tracks and steppe bison biogeographical distribution in Iberia. Aurochs were the most likely producers of the newly described Trafalgar Trampled Surface (TTS) and some of the large artiodactyl tracks in the Matalascañas Trampled Surface, representing the oldest aurochs track record known. This new evidence, together with comparisons with the record of possible aurochs tracks in the Mid-Late Pleistocene coastal deposits from the Asperillo cliff section in Matalascañas (Huelva Province, SW Spain) and bone assemblages known in Gibraltar, point to a recurrent use of the coastal habitat by these large artiodactyls in SW Iberia.


Assuntos
Bison , Cervos , Animais , Bovinos , Fósseis , Cabras , Espanha
8.
J Neurol Surg B Skull Base ; 83(1): 44-52, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35155069

RESUMO

Objectives This study aimed to establish the anatomical landmarks for performing a contralateral transmaxillary approach (CTM) to the petrous apex (PA) and petroclival region (PCR), and to compare CTM with a purely endoscopic endonasal approach (EEA). Design EEA and CTM to the PA and PCR were performed bilaterally in eight human anatomical specimens. Surgical techniques and anatomical landmarks were described, and EEA was compared with CTM with respect to ability to reach the contralateral internal acoustic canal (IAC). Computed tomographic scans of 25 cadaveric heads were analyzed and the "angle" and "reach" of CTM and EEA were measured. Results Entry to the PA via a medial approach was limited by (1) abducens nerve superiorly, (2) internal carotid artery (ICA) laterally, and (3) petroclival synchondrosis inferiorly (Gardner's triangle). With CTM, it was possible to reach the contralateral IAC bilaterally in all specimens dissected, without dissection of the ipsilateral ICAs, pterygopalatine fossae, and Eustachian tubes. Without CTM, reaching the contralateral IAC was possible only if: (1) angled endoscopes and instruments were employed or (2) the pterygopalatine fossa was dissected with mobilization of the ICA and resection of the Eustachian tube. The average "angle" and "reach" advantages for CTM were 25.6-degree greater angle of approach behind the petrous ICA and 1.4-cm more lateral reach. Conclusion The techniques and anatomical landmarks for CTM to the PA and PCR are described. Compared with a purely EEA, the CTM provides significant "angle" and "reach" advantages for the PA and PCR.

9.
Sci Rep ; 11(1): 17311, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531420

RESUMO

Tracks and trackways of newborns, calves and juveniles attributed to straight-tusked elephants were found in the MIS 5 site (Upper Pleistocene) known as the Matalascañas Trampled Surface (MTS) at Huelva, SW Spain. Evidence of a snapshot of social behaviour, especially parental care, can be determined from the concentration of elephant tracks and trackways, and especially from apparently contemporaneous converging trackways, of small juvenile and larger, presumably young adult female tracks. The size frequency of the tracks enabled us to infer body mass and age distribution of the animals that crossed the MTS. Comparisons of the MTS demographic frequency with the morphology of the fore- and hind limbs of extant and fossil proboscideans shed light into the reproductive ecology of the straight-tusked elephant, Palaeloxodon antiquus. The interdune pond habitat appeared to have been an important water and food resource for matriarchal herds of straight-tusked elephants and likely functioned as a reproductive habitat, with only the rare presence of adult and older males in the MTS. The preservation of this track record in across a paleosol surface, although heavily trampled by different animals, including Neanderthals, over a short time frame, permitted an exceptional view into short-term intraspecific trophic interactions occurring in the Last Interglacial coastal habitat. Therefore, it is hypothesized that Neanderthals visited MTS for hunting or scavenging on weakened or dead elephants, and more likely calves.


Assuntos
Elefantes/fisiologia , Animais , Animais Recém-Nascidos , Estatura , Peso Corporal , Ecossistema , Elefantes/anatomia & histologia , Feminino , Geografia , Humanos , Imageamento Tridimensional , Homem de Neandertal , Reprodução , Espanha
10.
Arq. bras. neurocir ; 40(3): 263-267, 15/09/2021.
Artigo em Inglês | LILACS | ID: biblio-1362153

RESUMO

Up to 20% of victims from skull fractures are represented by the pediatric population, and 50% of these lesions are depressed skull fractures. The treatment is multimodal in nature, ranging from conservative treatment to open surgical repair. The last one is associated, although in a small proportion, to complications, such as infections, hematomas and even death, besides the risks of the anesthetic procedure itself. The authors of the present article present a case report of the successful treatment of a depressed skull fracture in a newborn patient, using the vacuum-suction technique. The use of vacuum-suction may be beneficial for the pediatric patients, as it is a quick, non-invasive procedure, without the need for general anesthesia.


Assuntos
Humanos , Feminino , Recém-Nascido , Traumatismos do Nascimento/terapia , Fratura do Crânio com Afundamento/terapia , Fratura do Crânio com Afundamento/diagnóstico por imagem , Sucção/métodos , Vácuo , Resultado do Tratamento , Tratamento Conservador
11.
World Allergy Organ J ; 13(9): 100456, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32874426

RESUMO

BACKGROUND & AIMS: As far as we know, no screening questionnaire has been developed and validated for identification of adverse food reactions in Portuguese-speaking adults, as an initial approach towards the investigation of cases of possible food allergy. Thus, the objective of this study was to develop and validate a screening questionnaire of food allergy in adult Portuguese-speaking patients. METHODS: This was a multicentre, cross-sectional study using a simple random sample of 186 adults between 18 and 82 years old from various parts of the centre of Portugal. Intelligibility of the questionnaire was first assessed in 24 patients with confirmed IgE- or non-IgE-mediated food allergy, and in 24 volunteers without food allergies. The 17-item questionnaire was subsequently applied by phone to 78 food allergic patients (66 IgE-mediated and 12 non-IgE mediated) and to 60 non-food allergic volunteers, with subsequent reassessment (re-test). Face and content validity, intelligibility, construct validity, and test-retest reliability (temporal stability) were analysed. RESULTS: Face and content validity allowed item reduction from 30 to 17 items with adequate content validity index >0.78. Construct validity was confirmed in the 66 confirmed IgE-mediated food allergic patients, 12 non-IgE-mediated food allergic patients, and 60 non-allergic patients. Test-Retest Reliability (general temporal stability) of the test had a Spearman correlation coefficient value of 0.845 for the retest. Cohen's Kappa values for the relevant questions were greater than 0.890 for almost all items. No differences were found when sex, age, and volunteers' recruitment origin were analysed. An inverse relationship was found between reliability and retest time interval. CONCLUSIONS: Due to the quick and easy implementation, confirmation of face, content and construct validity as well as high temporal reproducibility, this screening questionnaire may be a useful study tool for an initial approach to detection of food allergies in adults.

13.
Oper Neurosurg (Hagerstown) ; 16(6): 734-742, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30649510

RESUMO

BACKGROUND: The endoscopic endonasal approach is a surgical alternative for midline anterior skull base tumors. A detailed understanding of the proximal anterior cerebral artery (ACA) branches' anatomy from an endonasal perspective is essential for avoiding vascular complications. OBJECTIVE: To evaluate, from an endonasal perspective, the anatomic variations of the ACA and its proximal branches, specifically the recurrent artery of Heubner (RAH), and the fronto-orbital (FOA) and frontopolar (FPA) arteries. METHODS: We study the origin, course, branching pattern, diameter, and relationship between the proximal ACA branches and the optic apparatus and olfactory tract in 25 head specimens. RESULTS: The RAH was present in all hemispheres and originated within 3 ± 1.5 mm of the AcomA, with a 0.4 ± 0.1 mm diameter. Based on its relationship with the A1 segment, we observed three RAH courses: anterior (40%), superior (22%), and posterior (38%). The FOA was present in all cases, a mean of 6 ± 4 mm from the AcomA, with a 0.7 ± 0.4 mm diameter. The FOA arose mainly from the A2 (70%), with three courses in relation to the olfactory tract: crossing its proximal third (54%), crossing its middle third (31%), and running parallel to it along the gyrus rectus (15%). The FPA was present in 92% of the hemispheres, a mean of 10 ± 5 mm from the AcomA, always arising from the A2 and coursing anteriorly within the interhemispheric fissure towards the frontal pole. CONCLUSION: The RAH, FOA, and FPA can be differentiated by origin, course, and destination using the A1 segment, olfactory tract, and interhemispheric fissure, respectively, as surgical landmarks.


Assuntos
Pontos de Referência Anatômicos , Variação Anatômica , Artéria Cerebral Anterior/anatomia & histologia , Cirurgia Endoscópica por Orifício Natural/métodos , Neuroendoscopia/métodos , Adulto , Artéria Cerebral Anterior/anormalidades , Cadáver , Humanos , Cavidade Nasal
14.
Oper Neurosurg (Hagerstown) ; 16(5): 600-606, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30107582

RESUMO

BACKGROUND: The treatment of cerebrospinal fluid leaks of the lateral recess of the sphenoid sinus (LRSS) faces difficulties due to the deep location of the osseous defect. When treated with craniotomies, brain retraction is a concern. The endoscopic endonasal transpterygoid approach (EETA) is a direct and less invasive procedure; however, it may require transection of the vidian nerve (VN). OBJECTIVE: To investigate the feasibility of a lateral transorbital approach (LTOA) as an alternative pathway to the LRSS that avoids VN sacrifice. METHODS: Six embalmed heads with well-pneumatized LRSS were preselected by inspecting their computed tomography scans. One LTOA and one EETA were performed on 1 side of each specimen. The approaches were compared regarding working distance and neurovascular structures being sacrificed. The working area of the LTOA was also measured. RESULTS: The average working distances were 59.9 (±2.94) mm for the LTOA and 76.4 (±3.99) mm for the EETA (P < .001). The LTOA generated a working area with a diameter of 9 to 14 mm. The EETA demanded the sacrifice of VN and the sphenopalatine artery in all specimens to expose the LRSS. No neurovascular structures were found in the trajectory of the LTOA. CONCLUSION: The LTOA to the LRSS is feasible, with minimal risk of injuring neurovascular structures. It offers a shorter pathway when compared to the EETA. Although the LTOA provides no options for vascularized flap reconstruction, it allows immediate access to muscle grafts. The LTOA may serve as an alternative to treating cerebrospinal fluid leaks of the LRSS.


Assuntos
Neuroendoscopia/métodos , Órbita/anatomia & histologia , Órbita/cirurgia , Seio Esfenoidal/anatomia & histologia , Seio Esfenoidal/cirurgia , Cadáver , Vazamento de Líquido Cefalorraquidiano/patologia , Vazamento de Líquido Cefalorraquidiano/cirurgia , Humanos , Nervo Mandibular/anatomia & histologia , Nervo Mandibular/patologia , Nervo Mandibular/cirurgia , Cavidade Nasal/anatomia & histologia , Cavidade Nasal/patologia , Cavidade Nasal/cirurgia , Órbita/patologia , Seio Esfenoidal/patologia
15.
Oper Neurosurg (Hagerstown) ; 16(3): 351-359, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30010967

RESUMO

BACKGROUND: Due to the critical neurovascular structures that surround the pulvinar, deciding the best surgical approach can be challenging, with multiple options available. OBJECTIVE: To analyze and compare the ipsilateral vs the contralateral version of the 2 main approaches to the cisternal pulvinar surface: paramedian supracerebellar infratentorial (PSCI) and interhemispheric occipital transtentorial (IOT). METHODS: The PSCI and IOT approaches were performed on 7 formalin-fixed adult cadaveric heads to evaluate qualitatively and quantitatively the microsurgical exposure of relevant anatomic structures. We quantitatively measured the corridor distance to our target with each approach. RESULTS: The ipsilateral PSCI approach provided an easier access and a better exposure of the anteromedial portion of the cisternal pulvinar surface. The contralateral approach provided a wider and more accessible exposure of the posterolateral portion of the cisternal pulvinar surface. When protrusion of the posterior parahippocampal gyrus above the free edge of the tentorium was present, the contralateral PSCI approach provided an unobstructed view to both areas. The IOT approach provided a better view of the anteromedial portion of the cisternal pulvinar surface, especially with a contralateral approach. CONCLUSION: Multiple approaches to the pulvinar have been described, modified, and improved. Based on this anatomic study we believe that although the corridor distance with a contralateral approach is longer, the surgical view and access can be better. We recommend the use of a PSCI contralateral approach especially when a significant protrusion of the posterior parahippocampal gyrus is present.


Assuntos
Microcirurgia/métodos , Procedimentos Neurocirúrgicos/métodos , Pulvinar/cirurgia , Craniotomia/métodos , Humanos
16.
Brain Struct Funct ; 224(2): 907-923, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30542766

RESUMO

We previously proposed a bipartite 'dorsal-ventral' model of human arcuate fasciculus (AF) morphology. This model does not, however, account for the 'vertical,' temporo-parietal subdivision of the AF described in earlier dissection and tractographic studies. In an effort to address the absence of the vertical AF (VAF) within 'dorsal-ventral' nomenclature, we conducted a dedicated tractographic and white-matter dissection study of this tract and another short, vertical, posterior-hemispheric fascicle: the vertical occipital fasciculus (VOF). We conducted atlas-based, non-tensor, deterministic tractography in 30 single subjects from the Human Connectome Project database and verified our results using an average diffusion atlas compiled from 842 separate normal subjects. We also performed white-matter dissection in four post-mortem specimens. Our  tractography results demonstrate that the VAF is, in fact, a bipartite system connecting the ventral parietal and temporal regions, with variable connective, and no volumetric lateralization. The VOF is a non-lateralized, non-segmented system connecting lateral occipital areas with basal-temporal regions. Importantly, the VOF was spatially dissociated from the VAF. As the VAF demonstrates no overall connective or volumetric lateralization, we postulate its distinction from the AF system and propose its re-naming to the 'temporo-parietal aslant tract,' (TPAT), with unique dorsal and ventral subdivisions. Our tractography results were supported by diffusion atlas and white-matter dissection findings.


Assuntos
Lobo Occipital/diagnóstico por imagem , Lobo Parietal/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Conectoma , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Vias Neurais/anatomia & histologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Lobo Occipital/anatomia & histologia , Lobo Occipital/fisiologia , Lobo Parietal/anatomia & histologia , Lobo Parietal/fisiologia , Lobo Temporal/anatomia & histologia , Lobo Temporal/fisiologia , Substância Branca/anatomia & histologia , Substância Branca/fisiologia , Adulto Jovem
17.
Oper Neurosurg (Hagerstown) ; 17(1): 79-87, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30561716

RESUMO

BACKGROUND: Suprachiasmatic subcallosal lesions may have an intimate relationship with the anterior communicating artery (AcomA); injury to AcomA branches can result in basal forebrain infarction and cognitive dysfunction. OBJECTIVE: To evaluate anatomic variations of the AcomA basal perforating branches, especially the subcallosal artery (ScA), for clinical implications when approaching the suprachiasmatic subcallosal region from endonasal and transcranial routes. METHODS: The origin, course, diameter, and branching pattern of the AcomA's perforating branches were studied in 33 specimens from transcranial and endonasal perspectives. RESULTS: The ScA was present in 79% of the specimens as a single dominant artery arising from the posterior/posterosuperior surface of the AcomA, along with hypothalamic arteries (55%), or as a single artery (24%). It coursed posteriorly towards the lamina terminalis region, curving superiorly to the subcallosal area. The ScA gave off many branches to provide the main blood supply to the subcallosal region. Importantly, it supplies the septal/subcallosal region bilaterally. The ScA can be found posterior, superior, or inferior to the AcomA when using a transylvian, interhemispheric, or endonasal approach, respectively. In specimens with no ScA (21%), the median callosal artery (MdCA) was the dominant artery arising from the AcomA. It followed an identical course to the ScA, providing supply to the same structures bilaterally, but its distal extension reached the body/splenium of the corpus callosum. The MdCA is a ScA variant. CONCLUSION: The ScA is a unique vessel because it supplies the septal/subcallosal region bilaterally; preservation of this vessel during surgery is crucial for successful outcomes.


Assuntos
Artérias Cerebrais/cirurgia , Neuroendoscopia/métodos , Córtex Pré-Frontal/cirurgia , Adenoma/cirurgia , Adulto , Cadáver , Artérias Cerebrais/anatomia & histologia , Feminino , Humanos , Aneurisma Intracraniano/cirurgia , Masculino , Meningioma/cirurgia , Microcirurgia/métodos , Pessoa de Meia-Idade , Neoplasias Hipofisárias/cirurgia , Córtex Pré-Frontal/anatomia & histologia
18.
J Neurosurg ; 131(1): 131-140, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30192191

RESUMO

OBJECTIVE: Pituitary adenomas often invade the medial wall of the cavernous sinus (CS), but this structure is generally not surgically removed because of the risk of vascular and cranial nerve injury. The purpose of this study was to report the surgical outcomes in a large series of cases of invasive pituitary adenoma in which the medial wall of the CS was selectively removed following an anatomically based, stepwise surgical technique. METHODS: The authors' institutional database was reviewed to identify cases of pituitary adenoma with isolated invasion of the medial wall, based on an intraoperative evaluation, in which patients underwent an endoscopic endonasal approach with selective resection of the medial wall of the CS. Cases with CS invasion beyond the medial wall were excluded. Patient complications, resection, and remission rates were assessed. RESULTS: Fifty patients were eligible for this study, 15 (30%) with nonfunctional adenomas and 35 (70%) with functional adenomas, including 16 growth hormone-, 10 prolactin-, and 9 adrenocorticotropic hormone (ACTH)-secreting tumors. The average tumor size was 2.3 cm for nonfunctional and 1.3 cm for functional adenomas. Radiographically, 11 cases (22%) were Knosp grade 1, 23 (46%) Knosp grade 2, and 16 (32%) Knosp grade 3. Complete tumor resection, based on intraoperative impression and postoperative MRI, was achieved in all cases. The mean follow-up was 30 months (range 4-64 months) for patients with functional adenomas and 16 months (range 4-30 months) for those with nonfunctional adenomas. At last follow-up, complete biochemical remission (using current criteria) without adjuvant treatment was seen in 34 cases (97%) of functional adenoma. No imaging recurrences were seen in patients who had nonfunctional adenomas. A total of 57 medial walls were removed in 50 patients. Medial wall invasion was histologically confirmed in 93% of nonfunctional adenomas and 83% of functional adenomas. There were no deaths or internal carotid artery injuries, and the average blood loss was 378 ml. Four patients (8%) developed a new, transient cranial nerve palsy, and 2 of these patients required reoperation for blood clot evacuation and fat graft removal. There were no permanent cranial nerve palsies. CONCLUSIONS: The medial wall of the CS can be removed safely and effectively, with minimal morbidity and excellent resection and remission rates. Further follow-up is needed to determine the long-term results of this anatomically based technique, which should only be performed by very experienced endonasal skull base teams.

19.
J Neurosurg ; 131(1): 122-130, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30192192

RESUMO

OBJECTIVE: The medial wall of the cavernous sinus (CS) is often invaded by pituitary adenomas. Surgical mobilization and/or removal of the medial wall remains a challenge. METHODS: Endoscopic endonasal dissection was performed in 20 human cadaver heads. The configuration of the medial wall, its relationship to the internal carotid artery (ICA), and the ligamentous connections in between them were investigated in 40 CSs. RESULTS: The medial wall of the CS was confirmed to be an intact single layer of dura that is distinct from the capsule of the pituitary gland and the periosteal layer that forms the anterior wall of the CS. In 32.5% of hemispheres, the medial wall was indented by and/or well adhered to the cavernous ICA. The authors identified multiple ligamentous fibers that anchored the medial wall to other walls of the CS and/or to specific ICA segments. These parasellar ligaments were classified into 4 groups: 1) caroticoclinoid ligament, spanning from the medial wall and the middle clinoid toward the clinoid ICA segment and anterior clinoid process; 2) superior parasellar ligament, connecting the medial wall to the horizontal cavernous ICA and/or lateral wall of the CS; 3) inferior parasellar ligament, bridging the medial wall to the anterior wall of the CS or anterior surface of the short vertical segment of the cavernous ICA; and 4) posterior parasellar ligament, which anchors the medial wall to the short vertical segment of the cavernous ICA and/or the posterior carotid sulcus. The caroticoclinoid ligament and inferior parasellar ligament were present in most CSs (97.7% and 95%, respectively), while the superior and posterior parasellar ligaments were identified in approximately half of the CSs (57.5% and 45%, respectively). The caroticoclinoid ligament was the strongest and largest ligament, and it was typically assembled as a group of ligaments with a fan-like arrangement. The inferior parasellar ligament was the first to be encountered after opening the anterior wall of the CS during an interdural transcavernous approach. CONCLUSIONS: The authors introduce a classification of the parasellar ligaments and their role in anchoring the medial wall of the CS. These ligaments should be identified and transected to safely mobilize the medial wall away from the cavernous ICA during a transcavernous approach and for safe and complete resection of adenomas that selectively invade the medial wall.

20.
World Neurosurg ; 113: e628-e637, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29486312

RESUMO

BACKGROUND: Integration of three-dimensional (3D) printing and stereolithography into clinical practice is in its nascence, and concepts may be esoteric to the practicing neurosurgeon. Currently, creation of 3D printed implants involves recruitment of offsite third parties. We explored a range of 3D scanning and stereolithographic techniques to create patient-specific synthetic implants using an onsite, clinician-facilitated approach. METHODS: We simulated bilateral craniectomies in a single cadaveric specimen. We devised 3 methods of creating stereolithographically viable virtual models from removed bone. First, we used preoperative and postoperative computed tomography scanner-derived bony window models from which the flap was extracted. Second, we used an entry-level 3D light scanner to scan and render models of the individual bone pieces. Third, we used an arm-mounted, 3D laser scanner to create virtual models using a real-time approach. RESULTS: Flaps were printed from the computed tomography scanner and laser scanner models only in a ultraviolet-cured polymer. The light scanner did not produce suitable virtual models for printing. The computed tomography scanner-derived models required extensive postfabrication modification to fit the existing defects. The laser scanner models assumed good fit within the defects without any modification. CONCLUSIONS: The methods presented varying levels of complexity in acquisition and model rendering. Each technique required hardware at varying in price points from $0 to approximately $100,000. The laser scanner models produced the best quality parts, which had near-perfect fit with the original defects. Potential neurosurgical applications of this technology are discussed.


Assuntos
Craniotomia/métodos , Impressão Tridimensional , Crânio/diagnóstico por imagem , Estereolitografia , Retalhos Cirúrgicos , Craniotomia/normas , Estudos de Viabilidade , Humanos , Impressão Tridimensional/normas , Crânio/patologia , Estereolitografia/normas , Retalhos Cirúrgicos/normas
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