Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Turk Neurosurg ; 33(5): 906-911, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37528723

RESUMO

AIM: To comprehensively analyze clinical presentation, diagnosis, and management approaches of brain tumors in infants under one year of age. MATERIAL AND METHODS: We conducted a retrospective analysis of clinical data retrieved from medical records of infants who underwent surgical treatment for intracranial mass lesions at our institution from January 2006 to December 2016. The data encompassed parameters such as age at diagnosis, symptoms, tumor location, histology, surgical procedures, adjuvant treatment, and survival outcomes. Cases involving dermoid, epidermoid cysts, and other skull-based lesions were excluded from the analysis. RESULTS: Our analysis identified twenty-three cases of brain tumors diagnosed within the first year of life, comprising 14 boys and 9 girls. The median age at diagnosis was 8.2 months, and the most common presenting symptoms were nausea and vomiting, as well as head circumference abnormalities. Successful gross total resection was achieved in 75.8% of patients, with choroid plexus papilloma being the most frequently encountered histopathological diagnosis. Eight patients received adjuvant chemotherapy, while one patient underwent salvage radiotherapy. CONCLUSION: The treatment of brain tumors in infants during their first year of life presents significant challenges. The affected patients exhibit diverse tumor pathologies occurring at various locations within the brain. Further research is warranted to establish optimal treatment options for this specific population.


Assuntos
Neoplasias Encefálicas , Masculino , Feminino , Humanos , Lactente , Estudos Retrospectivos , Neoplasias Encefálicas/cirurgia , Resultado do Tratamento , Quimioterapia Adjuvante , Cabeça
2.
Heliyon ; 9(7): e17838, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37456003

RESUMO

We report the functional assessment of tungsten (VI) oxide on gamma-ray attenuation properties of 60Sb2O3-(40-x)NaPO3-xWO3 antimony glasses. The elemental mass-fractions and glass-densities of each glass sample are specified separately for the MCNPX Monte Carlo code. In addition to fundamental gamma absorption properties, Transmission Factors throughout a broad radioisotope energy range were measured. According to findings, holmium (Ho) incorporation into the glass structure resulted in a net increase of 0.3406 g/cm3, whereas cerium (Ce) addition resulted in a net increase of 0.2047 g/cm3. The 40% WO3 reinforced S7 sample was found to have the greatest LAC value, even though seven glass samples exhibited identical behavior. The S2 sample had the lowest HVL values among the glass groups evaluated in this work, computed in the energy range of 0.015-15 MeV. The lowest EBF and EABF values were reported for 40% WO3 reinforced S7 sample with the highest LAC and density values. According to the findings of this research, WO3 will likely make a significant contribution to the gamma ray absorption properties of antimony glasses, which are employed for optical and structural modification. Therefore, it can be concluded that WO3 may be treated monotonically and can be employed successfully in circumstances where gamma-ray absorption characteristics, optical properties, and structural qualities need to be enhanced.

3.
Front Public Health ; 11: 1171209, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37064659

RESUMO

Introduction: A lead-acrylic protective screen is suggested to reduce radiation exposure to the unexposed breast during mammography. The presence of toxic lead in its structure may harm the tissues with which it comes in contact. This study aimed to design a CdO-rich quaternary tellurite glass screen (C40) and evaluate its efficiency compared to the Lead-Acrylic protective screen. Methods: A three-layer advanced heterogeneous breast phantom designed in MCNPX (version 2.7.0) general-purpose Monte Carlo code. Lead acrylic and C40 shielding screens were modeled in the MCNPX and installed between the right and left breast. The reliability of the absorption differences between the lead acrylic and C40 glass were assessed. Results and discussion: The results showed that C40 protective glass screen has much superior protection properties compared to the lead acrylic protective screen. The amount of total dose absorbed in the unexposed breast for C40 was found to be much less than that for lead-based acrylic. The protection provided by the C40 glass screen is 35-38% superior to that of the Lead-Acrylic screen. The C40 offer the opportunity to avoid the toxic Pb in the structure of Lead-Acrylic material and may be utilized for mammography to offer superior radioprotection to Lead-Acrylic and significantly lower the dose amount in the unexposed breast. It can be concluded that transparent glass screens may be utilized for radiation protection purposes in critical diagnostic radiology applications through mammography.


Assuntos
Proteção Radiológica , Proteção Radiológica/métodos , Doses de Radiação , Método de Monte Carlo , Benchmarking , Reprodutibilidade dos Testes , Mamografia/métodos
4.
Heliyon ; 9(3): e14274, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36950638

RESUMO

This study's primary objective is to provide the preliminary findings of novel research on the design of Indium (III) oxide-reinforced glass container that were thoroughly developed for the purpose of a nuclear material container for transportation and waste management applications. The shielding characteristics of an Indium (III) oxide-reinforced glass container with a certain elemental composition against the 60Co radioisotope was thoroughly evaluated. The energy deposition in the air surrounding the designed portable glass containers is measured using MCNPX general-purpose Monte Carlo code. Simulation studies were carried out using Lenovo-P620 workstation and the number of tracks was defined as 108 in each simulation phase. According to results, the indium oxide-doped C6 (TZI8) container exhibits superior protective properties compared to other conventional container materials such as 0.5Bitumen-0.5 Cement, Pb Glass composite, Steel-Magnetite concrete. In addition to its superiority in terms of nuclear safety, it is proposed that the source's simultaneous observation and monitoring, as well as the C6 (TZI8) glass structure's transparency, be underlined as significant advantages. High-density glasses, which may replace undesirable materials such as concrete and lead, provide several advantages in terms of production ease, non-toxic properties, and resource monitoring. In conclusion, the use of Indium (III) oxide-reinforced glass with its high transparency and outstanding protection properties may be a substantial choice in places where concrete is required to ensure the safety of nuclear materials.

5.
Turk J Med Sci ; 52(4): 1235-1240, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36326359

RESUMO

BACKGROUND: Craniosynostosis is a deformity of the skull that occurs as a result of early fusion of one or more cranial sutures and can be accompanied by neurological deficits. Craniosynostosis can be classified as syndromic or nonsyndromic according to the type of suture involved. Surgical treatment of craniosynostosis in infants basically involves loosening and opening the fused sutures to reduce intracranial pressure, allow the brain to grow, and also fix the skull shape. However, in such cases there is a risk of resynostosis after surgery. According to the literature, resynostosis rates vary between 0% and 70%. In this study, we aimed to evaluate the reoperation rate in craniosynostosis cases treated surgically in our clinic. METHODS: A retrospective analysis of 70 nonsyndromic craniosynostosis cases treated surgically in the Neurosurgery Department of Bursa Uludag University from 2005 to 2019 was performed. All patients had undergone total cranial vault remodeling surgically and had been followed up for at least a year. RESULTS: The study group included 70 patients, comprising 40 (57.1%) male and 30 (42.9%) female patients. The mean age of the group was 10.9 ± 7.8 months (range 3-34 months). Out of 70 patients, repeat surgery due to resynostosis had been performed once in 5 (7.1%) patients and twice in 1 (1.4%) patient. DISCUSSION: It should be kept in mind that resynostosis may occur in patients who have been operated for craniosynostosis. Patients should be examined cosmetically and if necessary, radiologically in the follow-up. Further studies based on larger sample size are recommended for more quantitative data and better results.


Assuntos
Craniossinostoses , Tomografia Computadorizada por Raios X , Lactente , Humanos , Masculino , Feminino , Pré-Escolar , Reoperação , Estudos Retrospectivos , Craniossinostoses/cirurgia , Suturas Cranianas/cirurgia
6.
J Neurol Surg B Skull Base ; 83(Suppl 3): e606-e607, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36068888

RESUMO

Fusiform or near-fusiform aneurysms that involve the long segment of the supraclinoid internal carotid artery (ICA) pose significant challenges to neurovascular surgeons. Involvement of the origin of vital branching arteries in this segment may preclude safe treatment with flow diverting stents. In addition, clip reconstruction may also not be possible in this region due to entire or near-entire involvement of the circumference of the ICA ( Fig. 1 ). In this video article, we present a case of a complex and previously leaked, (visualized with hemosiderin) aneurysm of the posterior communicating segment of the ICA, in a 60-year-old female. Multiple complexities made this aneurysm challenging to treat. These included (1) a 270-degree encirclement of the ICA with multiple lobulations that left only a small section of nondiseased vessel wall, (2) a relatively short segment of the supraclinoidal ICA that made proximal control challenging thus requiring an extradural anterior clinoidectomy, (3) a fetal posterior communicating artery that originated immediately proximal to the beginning of the aneurysm, and lastly, (4) an anterior choroidal artery that was firmly adherent over the aneurysm dome. In this video, we present the microsurgical steps for dealing with this complex aneurysm, including extradural clinoidectomy and clip reconstruction ( Fig. 2 ). Postoperatively, the patient woke up without any deficits. Angiography showed complete obliteration of the aneurysm. The link to the video can be found at: https://youtu.be/3Zz-ecvlDIc .

7.
J Neurol Surg B Skull Base ; 83(Suppl 3): e616-e618, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36092496

RESUMO

Surgical treatment of giant aneurysms often poses significant challenges. Endovascular techniques have evolved exponentially over the last decades, and most of these complex aneurysms can be treated with flow-diverting techniques; however, successful obliteration of all giant aneurysms is not always possible with endovascular flow-diverting techniques. Although the need for microsurgical intervention has undoubtedly diminished, a versatile-thinking surgeon should keep in mind that obliteration of these aneurysms combined with revascularizing the distal circulation via extracranial-intracranial bypass techniques can provide a potentially life-long durable solution. The key to curing these pathologies is to utilize interdisciplinary decision making with a robust knowledge of the pros and cons of different treatment approaches. Herein, we present a case of a giant posterior communicating segment aneurysm of the left supraclinoid internal carotid artery (ICA), which was treated by obliteration ( Fig. 1 ). Extradural anterior clinoidectomy was used to provide exposure of the supraclinoidal ICA proximal to the aneurysm, and revascularization of the distal circulation was achieved with a common carotid artery to M2-superior trunk bypass using a radial artery interposition graft ( Fig. 2 ). The patient was a 62-year-old female who presented with vision loss in her left eye but was otherwise neurologically intact. She had a history of two unsuccessful flow-diverting stent placement attempts 2 months prior to this surgery. Postoperatively, the patient woke up without any deficits, with her left eye vision partially recovered and ultimately returning to normal at 1-year follow-up. Computed tomography (CT) angiography at a 1-year follow-up showed complete obliteration of the aneurysm and successful revascularization of the distal circulation. The link to the video can be found at: https://youtu.be/DsIuIJJj1l4 .

8.
Anat Sci Int ; 96(2): 294-300, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33400249

RESUMO

The chiasmal and subchiasmal surfaces are of critical importance in connection with the performance of surgical procedures owing to the critical blood supply to these areas. Recently, the perforating arteries providing the blood to the optic nerves and chiasm have gained attention as they significantly affect the morbidity from surgical approaches. Intraoperative preservation of these perforating arteries is considered critical to prevent further visual loss. Thirty autopsy specimens, including the optic apparatus, were examined for their perforating arteries feeding the optic chiasm and optic nerves. The optic nerves and chiasmal surfaces were divided into four zones based on the presence and numbers of perforating arteries as anterior superior-posterior superior surfaces and anterior inferior-posterior inferior surfaces. The superior surface of the optic chiasm was supplied by the A1 segments of the bilateral anterior cerebral arteries and by the perforating arteries originating from the anterior communicating artery. On the other hand, the inferior surface of the optic chiasm was fed by the bilateral posterior communicating arteries and by the supraclinoidal segments of the bilateral carotid arteries. We demonstrated the anatomical involvement of a large number of nourishing arteries in feeding the optic apparatus related to the perforating arteries by classifying them into zones based on the surgical approaches, which has been rarely reported in the literature.


Assuntos
Artérias Cerebrais/anatomia & histologia , Círculo Arterial do Cérebro/anatomia & histologia , Quiasma Óptico/irrigação sanguínea , Nervo Óptico/irrigação sanguínea , Cadáver , Humanos
9.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 31(3): 112-118, mayo-jun. 2020. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-192415

RESUMO

OBJECTIVE: Understanding the relationship between the carotid artery, optic nerve and the anterior clinoid process is the basis of surgical approaches performed in the subchiasmal region. The location of the optic chiasm, the length of the optic nerves, and the distance and angle between the optic nerves determine the route of surgical approaches. We have determined the types of optic chiasm to study the relationship between vascular and neural structures in this region. MATERIALS AND METHODS: Thirty autopsy specimens were investigated at the Bursa Forensic Medicine Institute for optic chiasm types and the relationship between the neural and vascular anatomical structures of the sellar-parasellar and subchiasmal region was examined between June 2016 and November 2016. RESULTS: In this study, 4 prefix types (13%), 6 postfix types (20%), and 20 central types (67%) of chiasm were defined. Furthermore, we measured this angle between two optic nerves, which indirectly shows the location of chiasm according to the diaphragma sellae, and then detected the mean value of this angle as 87.1 ± 11.6°. The "limit" value to designate a chiasm as prefix was measured in the current study as ≥ 101.1°. The angle between optic nerves ranged from a mean value of 69.9 ± 3.7° in 6 cases with postfix chiasm, to a mean value of 104.0±2.1° in 4 cases with prefix chiasm and a mean value of 88.8 ± 6.7° in 20 cases with central chiasm. CONCLUSIÓN: In this study, we showed that the relationship among optic chiasma types, optic nerves and bony and vascular structures around the sellar area was effective at determining the surgical approach to this región


OBJETIVO: Comprender la relación entre la arteria carótida, el nervio óptico y la apófisis clinoides anterior es la base de los tratamientos quirúrgicos realizados en la región subquiasmática. La ubicación del quiasma óptico, la longitud de los nervios ópticos, y la distancia y el ángulo entre dichos nervios determinan la vía de acceso quirúrgico. Hemos determinado los tipos de quiasma óptico para estudiar la relación entre las estructuras vasculares y neurales en esta región. MATERIALES Y MÉTODOS: Entre junio y noviembre de 2016, se analizaron 30 muestras de autopsia en el Instituto de Medicina Legal de Bursa (Turquía) para determinar los tipos de quiasma óptico, y examinar la relación entre las estructuras anatómicas neurales y vasculares de las regiones selar-paraselar y subquiasmática. RESULTADOS: En este estudio, se definieron 4 casos de quiasma prefijado (13%), 6 de quiasma posfijado (20%) y 20 de quiasma central (67%). Además, medimos el ángulo entre 2 nervios ópticos que muestra indirectamente la ubicación del quiasma según el diafragma selar, y luego detectamos el valor medio de este ángulo (87,1 ± 11,6°). El valor «límite» para designar un quiasma como «prefijado» se midió en el estudio actual como ≥ 101,1°. El valor medio del ángulo entre los nervios ópticos osciló entre 69,9 ± 3,7° en los 6 casos de quiasma posfijado, 104,0 ± 2,1° en los 4 casos de quiasma prefijado y 88,8 ± 6,7° en los 20 casos de quiasma central. CONCLUSIÓN: En este estudio, pusimos de manifiesto que la relación entre los tipos de quiasma óptico, los nervios ópticos y las estructuras óseas y vasculares alrededor del área selar fue eficaz para determinar el acceso quirúrgico en esta región


Assuntos
Humanos , Variação Anatômica , Quiasma Óptico/anatomia & histologia , Nervo Óptico/anatomia & histologia , Artérias Carótidas/anatomia & histologia , Cadáver , Quiasma Óptico/cirurgia , Nervo Óptico/cirurgia , Artérias Carótidas/cirurgia , Autopsia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos
10.
Childs Nerv Syst ; 36(2): 379-384, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31243581

RESUMO

PURPOSE: Surgery is the first treatment option for patients with metopic craniosynostosis. Fronto-orbital advancement is the preferred method for correction of isolated trigonocephaly, but it is hard to understand whether surgery has been successful mainly in an early period. We aim to investigate the shape differences in the head shapes of trigonocephaly patients compared between preoperative and postoperative term. METHODS: Cranial shape data were collected from the two-dimensional digital images. The Generalized Procrustes analysis was used to obtain mean shapes of the preoperative and postoperative term. The shape deformation of the frontal calvarium from preoperative to the postoperative term was evaluated using the thin-plate spline (TPS) method. RESULTS: There was significant cranial shape difference between preoperative and postoperative term. The high-level deformations for preoperative to postoperative term determined seen in TPS graphic. Highest deformation was observed at the bifrontal dimension especially at nasion and posterior edge of the forehead. CONCLUSIONS: In this study, we showed that the shape difference and structural deformation of the calvarium were correlated with the metopic craniosynostosis. The present study also shows that preoperative and postoperative head shapes of patients with trigonocephaly can be compared using the landmark-based geometrical morphometric method by taking into consideration the topographic distribution.


Assuntos
Craniossinostoses , Crânio , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Cabeça , Humanos , Lactente , Período Pós-Operatório , Projetos de Pesquisa , Crânio/anatomia & histologia , Crânio/cirurgia
11.
Neurocirugia (Astur : Engl Ed) ; 31(3): 112-118, 2020.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31780111

RESUMO

OBJECTIVE: Understanding the relationship between the carotid artery, optic nerve and the anterior clinoid process is the basis of surgical approaches performed in the subchiasmal region. The location of the optic chiasm, the length of the optic nerves, and the distance and angle between the optic nerves determine the route of surgical approaches. We have determined the types of optic chiasm to study the relationship between vascular and neural structures in this region. MATERIALS AND METHODS: Thirty autopsy specimens were investigated at the Bursa Forensic Medicine Institute for optic chiasm types and the relationship between the neural and vascular anatomical structures of the sellar-parasellar and subchiasmal region was examined between June 2016 and November 2016. RESULTS: In this study, 4 prefix types (13%), 6 postfix types (20%), and 20 central types (67%) of chiasm were defined. Furthermore, we measured this angle between two optic nerves, which indirectly shows the location of chiasm according to the diaphragma sellae, and then detected the mean value of this angle as 87.1±11.6°. The "limit" value to designate a chiasm as prefix was measured in the current study as ≥101.1°. The angle between optic nerves ranged from a mean value of 69.9±3.7° in 6 cases with postfix chiasm, to a mean value of 104.0±2.1° in 4 cases with prefix chiasm and a mean value of 88.8±6.7° in 20 cases with central chiasm. CONCLUSION: In this study, we showed that the relationship among optic chiasma types, optic nerves and bony and vascular structures around the sellar area was effective at determining the surgical approach to this region.


Assuntos
Quiasma Óptico , Nervo Óptico , Cadáver , Artérias Carótidas , Humanos , Quiasma Óptico/anatomia & histologia , Nervo Óptico/anatomia & histologia , Base do Crânio
12.
J Craniofac Surg ; 30(6): 1683-1685, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31033761

RESUMO

The surgical procedure is viewed as a typical treatment choice for patients with Chiari malformation (CM). Decompression is the preferred method for surgery, but it is not always possible to understand whether decompression has been successful especially in an early period. The present study focuses on investigating the shape differences in the cerebellums of Chiari patients compared with healthy controls, and to assess the clinical application of this situation whether if present. The MRI scans were reviewed retrospectively. Cerebellar data were obtained from the digital images and 9 anthropometric landmarks were marked on each image. Shape difference was assessed by performing Generalized Procrustes analysis. The cerebellar shape deformation from control to the patient was evaluated performing the Thin Plate Spline approach. There is a statistically significant cerebellar shape difference between groups. Highest deformation was determined at the cerebellar tonsillar inferior area, posterior of the uvula, and anterior of inferior medullary velum. The present study demonstrated cerebellar shape differences in CM I patients using a landmark-based geometric morphometric approach, considering the topographic distribution of cerebellum for the first time.


Assuntos
Malformação de Arnold-Chiari/diagnóstico por imagem , Malformação de Arnold-Chiari/cirurgia , Cerebelo/diagnóstico por imagem , Cerebelo/cirurgia , Adolescente , Adulto , Descompressão Cirúrgica , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Estudos Retrospectivos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...