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1.
Artículo en Inglés | MEDLINE | ID: mdl-38804569

RESUMEN

BACKGROUND: To evaluate the efficacy of a catheter system using a 3-Fr sheath with a steerable microcatheter through right upper limb artery access for superselective intra-arterial cisplatin infusion and concomitant radiotherapy (RADPLAT) to treat right maxillary sinus squamous cell carcinoma (MS-SCC). MATERIAL AND METHODS: We retrospectively studied 46 sessions in eight patients treated between November 2020 and February 2023 using the catheter system briefly described below. A 3-Fr sheath was inserted into the distal radial, conventional radial, or brachial arteries. A coaxial catheter system with a 2.9-Fr steerable microcatheter and a 1.9-Fr microcatheter was advanced into the brachiocephalic artery. The right common carotid artery was selected by bending the tip of the steerable microcatheter. Coil embolization and intra-arterial cisplatin infusion after selecting each external carotid artery branch were achieved using this catheter system. RESULTS: Cisplatin infusion and coil embolization were successful in all sessions. Arterial occlusion at the sheath insertion sites was found in 29.4% (5/17) of the distal radial arteries and 33.3% (3/9) of the conventional radial arteries. No other major complications were observed during the procedure. CONCLUSION: Using a 3-Fr catheter system with a steerable microcatheter through right upper limb artery access is a feasible method for RADPLAT in treating right MS-SCC.

2.
Nanotechnology ; 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35584615

RESUMEN

Transition metal dichalcogenides (TMDCs) are versatile layered materials with potential applications ranging from optoelectronic devices to water splitting. Top-down fabrication methods such as exfoliation are not practical for a large-scale production of high-quality devices: a bottom-up approach such as sputtering, a low-temperature deposition method, is more suitable. However, due to its anisotropic nature, the growth mechanism of molybdenum disulfide (MoS2) via sputtering is complex and remains to be investigated in detail. In this paper, we study the growth of MoS2 films co-deposited by using a sulfur (S) hot-lip cell and a molybdenum (Mo) sputtering target via reactive sputtering. The impact of S partial pressure on the structure and morphology of MoS2films was systematically characterized, and it was observed that the growth is dominated by vertically-oriented sheets with horizontal branches, resulting in a tree-like structure. The growth front of the structures is ascribed to the anisotropic incorporation of adatoms with regards to the orientation of MoS2.

3.
Sci Technol Adv Mater ; 19(1): 336-369, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29707072

RESUMEN

Photovoltaic generation has stepped up within the last decade from outsider status to one of the important contributors of the ongoing energy transition, with about 1.7% of world electricity provided by solar cells. Progress in materials and production processes has played an important part in this development. Yet, there are many challenges before photovoltaics could provide clean, abundant, and cheap energy. Here, we review this research direction, with a focus on the results obtained within a Japan-French cooperation program, NextPV, working on promising solar cell technologies. The cooperation was focused on efficient photovoltaic devices, such as multijunction, ultrathin, intermediate band, and hot-carrier solar cells, and on printable solar cell materials such as colloidal quantum dots.

4.
Hepatogastroenterology ; 61(136): 2200-2, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25699350

RESUMEN

An 85-year-old woman was referred to the medical oncology department because of a hypogastric mass. Contrast-enhanced CT showed a large hypervascular mass in the lower abdomen. CT angiography with volume rendering imaging revealed a vascular pedicle with an arborizing pattern of vessels. Many thick, early draining veins shunting into the portal vein were detected. Before surgery, the maximum size of the portal vein was 22 mm in diameter. Laparotomy revealed a huge, encapsulated, well-defined, hard tumor with hypervascularization, which was appended to the omentum. The mass with the omentum was curatively resected; it was 19 cm x 17 cm x 13 cm in size and 1915 g in weight. Histological features were consistent with a benign solitary fibrous tumor of the omentum, despite the tumor size and necrotic area found in the specimen. q Ultrasonography and CT performed at a 28-month follow-up revealed no evidence of tumor recurrence. Venous dilatation including that of the portal veins had diminished.


Asunto(s)
Neoplasias de Tejido Fibroso/patología , Epiplón , Neoplasias Peritoneales/patología , Vena Porta/patología , Anciano , Anciano de 80 o más Años , Dilatación Patológica , Femenino , Humanos , Vasodilatación
5.
Cureus ; 16(3): e55916, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38601366

RESUMEN

Aim  This study aimed to evaluate the diagnostic feasibility of magnetic resonance imaging (MRI) findings and texture features (TFs) for differentiating uterine endometrial carcinoma from uterine carcinosarcoma. Methods This retrospective study included 102 patients who were histopathologically diagnosed after surgery with uterine endometrial carcinoma (n=68) or uterine carcinosarcoma (n=34) between January 2008 and December 2021. We assessed conventional MRI findings and measurements (cMRFMs) and TFs on T2-weighted images (T2WI) and apparent diffusion coefficient (ADC) map, as well as their combinations, in differentiating between uterine endometrial carcinoma and uterine carcinosarcoma. The least absolute shrinkage and selection operator (LASSO) was used to select three features with the highest absolute value of the LASSO regression coefficient for each model and construct a discriminative model. Binary logistic regression analysis was used to analyze the disease models and conduct receiver operating characteristic analyses on the cMRFMs, T2WI-TFs, ADC-TFs, and their combined model to compare the two diseases. Results A total of four models were constructed from each of the three selected features. The area under the curve (AUC) of the discriminative model using these features was 0.772, 0.878, 0.748, and 0.915 for the cMRFMs, T2WI-TFs, ADC-TFs, and a combined model of cMRFMs and TFs, respectively. The combined model showed a higher AUC than the other models, with a high diagnostic performance (AUC=0.915). Conclusion A combined model using cMRFMs and TFs might be helpful for the differential diagnosis of uterine endometrial carcinoma and uterine carcinosarcoma.

6.
Nanotechnology ; 24(28): 285301, 2013 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-23787817

RESUMEN

We successfully fabricated defect-free, distributed and sub-20-nm GaAs quantum dots (named GaAs nanodisks (NDs)) by using a novel top-down technique that combines a new bio-template (PEGylated ferritin) and defect-free neutral beam etching (NBE). Greater flexibility was achieved when engineering the quantum levels of ND structures resulted in greater flexibility than that for a conventional quantum dot structure because structures enabled independent control of thickness and diameter parameters. The ND height was controlled by adjusting the deposition thickness, while the ND diameter was controlled by adjusting the hydrogen-radical treatment conditions prior to NBE. Photoluminescence emission due to carrier recombination between the ground states of GaAs NDs was observed, which showed that the emission energy shift depended on the ND diameters. Quantum level engineering due to both diameter and thickness was verified from the good agreement between the PL emission energy and the calculated quantum confinement energy.


Asunto(s)
Arsenicales/química , Galio/química , Nanoestructuras/química , Nanotecnología/métodos , Puntos Cuánticos , Biotecnología/métodos , Ferritinas/química , Microscopía Electrónica de Rastreo , Nanoestructuras/ultraestructura , Tamaño de la Partícula , Polietilenglicoles/química
7.
Neuroradiology ; 55(5): 585-94, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23344682

RESUMEN

INTRODUCTION: The origin of the vertebral artery (VA) varies, though most VAs enter the transverse foramen (TF) of the sixth cervical vertebra. On computed tomography (CT) angiographic images, we evaluated the prevalence of variations of both VA origin and its level of entry into the TF. METHODS: We retrospectively reviewed CT angiographic images of 2,287 patients obtained using either of two 64-slice multidetector CT scanners. All patients were Japanese and underwent scanning from the aortic arch to the intracranial region; most had or were suspected of having cerebrovascular diseases. RESULTS: The left VA (LVA) arose from the aorta between the left common carotid artery and left subclavian artery in 94 patients (4.1 %) and in other variations in 44 patients (1.9 %). The right VA (RVA) arose from the extreme proximal segment of the right subclavian artery in 72 patients (3.1 %) and in other variations in 14 patients (0.6 %). The LVA entered the sixth TF in 2,127 patients (93.0 %), and the RVA entered the sixth TF in 2,146 patients (93.8 %). Anomalous origin and anomalous entry level into the TF correlated strongly. CONCLUSIONS: The total prevalence of variation in the origin of the LVA was 6.0 % and of the RVA, 3.8 %. The total prevalence of variation in entry level into the TF was 7.0 % for the LVA and 6.2 % for the RVA. Recognition and reporting of these variations is important in interpreting CT angiography to prevent complications during surgery of the aortic arch or lower neck.


Asunto(s)
Angiografía/estadística & datos numéricos , Vértebras Cervicales/irrigación sanguínea , Vértebras Cervicales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Malformaciones Vasculares/diagnóstico por imagen , Arteria Vertebral/anomalías , Arteria Vertebral/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Malformaciones Vasculares/epidemiología
8.
Neuroradiology ; 55(1): 17-23, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22821359

RESUMEN

INTRODUCTION: Persistent hypoglossal artery (PHA) is the second most common anastomosis between the carotid and vertebrobasilar systems and demonstrates some variations. We evaluated the prevalence of PHA on computed tomography (CT) angiography. We also evaluated characteristic features of PHA and its variants on magnetic resonance (MR) angiography. METHODS: We retrospectively reviewed our database of 2,074 CT angiographic images obtained using either of two 64-slice multidetector CT scanners. We also reviewed our database of 7,646 MR angiographic images obtained using either of two 1.5-T or one 3.0-T imager. We could not determine the exact number of patients whose MR angiography included the hypoglossal canal. Most patients had or were suspected of having cerebrovascular diseases. RESULTS: We found six usual PHAs arising from the cervical internal carotid artery on CT angiography among 2,074 patients. On MR angiography, we also found six additional usual PHAs (total 12, right/left = 6/6, male/female = 3/9), three right PHAs originating from the external carotid artery (ECA), and two posterior inferior cerebellar arteries (PICAs) arising from the ECA without connection to the vertebral artery. CONCLUSIONS: The prevalence of usual PHA diagnosed by CT angiography was 0.29 %, slightly higher than that reported for angiography and may be due to selection bias in the examined patients. We propose naming usual PHA "type 1 PHA"; PHA originating from the ECA, of which we found three, "type 2 PHA"; and PICA arising from the ECA, of which we found two, "type 2 PHA variant."


Asunto(s)
Fístula Arterio-Arterial/diagnóstico , Fístula Arterio-Arterial/embriología , Arteria Basilar/anomalías , Arterias Carótidas/anomalías , Angiografía por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fístula Arterio-Arterial/cirugía , Arteria Basilar/diagnóstico por imagen , Arteria Basilar/patología , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/patología , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Adulto Joven
9.
Surg Radiol Anat ; 35(4): 339-42, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23129264

RESUMEN

INTRODUCTION: The left common carotid artery (LCCA) is usually a second branch of the aortic arch that arises between the brachiocephalic trunk (BCT) and left subclavian artery; relatively frequently, it also arises from or shares a common origin with the BCT. In patients with LCCA of anomalous origin, transfemoral catheterization into the LCCA is sometimes difficult, and transbrachial or transradial approach may be recommended. We evaluated the prevalence of these variations on computed tomography (CT) angiography. METHODS: We retrospectively reviewed CT angiographic images of 2,357 patients obtained using either of two 64-slice multidetector CT scanners. All patients were Japanese and underwent scanning from the aortic arch to the intracranial region; most had or were suspected of having cerebrovascular diseases. RESULTS: We evaluated CT angiographic images of 2,352 patients after excluding four patients with LCCA occluded at its origin. The LCCA arose from the BCT in 141 patients (6.0 %) and had a common origin with the BCT in 130 patients (5.5 %). We found 11 aberrant right subclavian artery (0.47 %), and four of the 11 patients (36 %) had LCCA of common origin with the right common carotid artery, forming a bicarotid trunk (prevalence: 0.17 %). CONCLUSIONS: The total prevalence of variations of LCCA origin diagnosed by CT angiography was 11.7 %.


Asunto(s)
Arteria Carótida Común/anatomía & histología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Variación Anatómica , Angiografía , Arteria Carótida Común/diagnóstico por imagen , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Adulto Joven
10.
Heliyon ; 9(8): e19312, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37664730

RESUMEN

In this work, we have experimentally investigated the impact of light trapping on the performance of InAs/GaAs quantum dot (QD) solar cells. To increase the amount of absorbed near-infrared photons, we fabricated a thin-film QD solar cell with a backside mirror where the positions of the QD layers were matched with the intensity peaks of one of the Fabry-Perot (FP) resonances in this structure to enable enhanced QD absorption near 1192 nm. We demonstrate that the external quantum efficiency at a given FP resonance wavelength of such an InAs/GaAs-based QD solar cell can be increased by an order of magnitude over solar cells without FP resonance by optimally positioning the QD layers.

11.
ACS Omega ; 8(25): 22414-22427, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37396253

RESUMEN

As a well-explored chalcopyrite material, copper gallium sulfide CGS has been considered a potential material for solar cell absorber layers. However, its photovoltaic attributes still require to be improved. In this research, a novel chalcopyrite material, copper gallium sulfide telluride CGST, has been deposited and verified as a thin film absorber layer to fabricate high-efficiency solar cells by experimental testing and numerical simulations. The results display the intermediate band formation in CGST with incorporation of Fe ions. Electrical studies showed enhancement in mobility from 1.181 to 1.473 cm2 V-1 s-1 and conductivity from 2.182 to 5.952 S cm-1 for pure and 0.08 Fe-substituted thin films. The I-V curves display the photoresponse and ohmic nature of the deposited thin films, and the maximum photoresponsivity (0.109 A W-1) was observed for 0.08 Fe-substituted films. Theoretical simulation of the prepared solar cells was carried out using SCAPS-1D software, and the obtained efficiency displayed an increasing trend from 6.14 to 11.07% as the Fe concentration increased from 0.0 to 0.08. This variation in efficiency is attributed to the decrease in bandgap (2.51-1.94 eV) and the formation of an intermediate band in CGST with Fe substitution, which is evidenced in UV-vis spectroscopy. The above revealed results open the way to 0.08 Fe-substituted CGST as a promising candidate as a thin film absorber layer in solar photovoltaic technology.

12.
Adv Mater ; 35(38): e2301834, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37311157

RESUMEN

A deep understanding of the effect of the A-site cation cross-exchange on the hot-carrier relaxation dynamics in perovskite quantum dots (PQDs) has profound implications on the further development of disruptive photovoltaic technologies. In this study, the hot carrier cooling kinetics of pure FAPbI3 (FA+ , CH(NH2 )2 + ), MAPbI3 (MA+ , CH3 NH3 + + ), CsPbI3 (Cs+ , Cesium) and alloyed FA0.5 MA0.5 PbI3 , FA0.5 Cs0.5 PbI3 , and MA0.5 Cs0.5 PbI3 QDs are investigated using ultrafast transient absorption (TA) spectroscopy. The lifetimes of the initial fast cooling stage (<1 ps) of all the organic cation-containing PQDs are shorter than those of the CsPbI3 QDs, as verified by the electron-phonon coupling strength extracted from the temperature-dependent photoluminescence spectra. The lifetimes of the slow cooling stage of the alloyed PQDs are longer under illumination greater than 1 sun, which is ascribed to the introduction of co-vibrational optical phonon modes in the alloyed PQDs. This facilitated efficient acoustic phonon upconversion and enhanced the hot-phonon bottleneck effect, as demonstrated by first-principles calculations.

13.
Acta Biomater ; 162: 110-119, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36924877

RESUMEN

The scaly-foot gastropod (Chrysomallon squamiferum), which lives in the deep-sea zone of oceans around thermal vents, has a black shell and scales on the foot. Both the black shell and scales contain iron sulfide minerals such as greigite (Fe3S4) and pyrite (FeS2). Although pyrite nanoparticles can be used as materials for solar panels, it is difficult to synthesize stable and spherical nanoparticles in vitro. In this study, we extracted organic molecules that interact with nano-pyrite from the shell of the scaly-foot gastropod to develop a low-cost, eco-friendly method for pyrite nanoparticles synthesis. Myoglobin (csMG), a heme protein, was identified in the iron sulfide layer of the shell. We purified recombinant csMG (r-csMG) and demonstrated that r-csMG helped in the conversion of ferric ions, sulfide ions and sulfur into spherical shaped pyrite nanoparticles at 80°C. To reduce the effort and cost of production, we showed that commercially available myoglobin from Equus caballus (ecMG) also induced the in vitro synthesis of pyrite nanoparticles. Using structure-function experiments with digested peptides, we highlighted that the amino acid sequence of r-csMG peptides controlled the spherical shape of the nanoparticle while the hemin molecules, which the peptides interacted with, maintained the size of nanoparticles. Synthesized pyrite nanoparticles exhibited strong photoluminescence in the visible wavelength region, suggesting its potential application as a photovoltaic solar cell material. These results suggest that materials for solar cells can be produced at low cost and energy under eco-friendly conditions. STATEMENT OF SIGNIFICANCE: Pyrite is a highly promising material for photovoltaic devices because of its excellent optical, electrical, magnetic, and transport properties and high optical absorption coefficient. Almost all current pyrite synthesis methods use organic solvents at high temperature and pressure under reducing conditions. Synthesized pyrite nanoparticles are unstable and are difficult to use in devices. The scaly-foot gastropod can synthesize pyrite nanoparticles in vivo, meaning that pyrite nanoparticles can be generated in an aqueous environment at low temperature. In this study, we demonstrated the synthesis of pyrite nanoparticles using a heme protein identified in the iron sulfide layer of the scaly-foot gastropod shell. These results exemplify how natural products in organisms can inspire the innovation of new technology.


Asunto(s)
Gastrópodos , Nanopartículas , Animales , Caballos , Mioglobina , Sulfuros/química
14.
Nanotechnology ; 23(6): 065302, 2012 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-22248504

RESUMEN

A sub-10 nm, high-density, periodic silicon-nanodisc (Si-ND) array has been fabricated using a new top-down process, which involves a 2D array bio-template etching mask made of Listeria-Dps with a 4.5 nm diameter iron oxide core and damage-free neutral-beam etching (Si-ND diameter: 6.4 nm). An Si-ND array with an SiO(2) matrix demonstrated more controllable optical bandgap energy due to the fine tunability of the Si-ND thickness and diameter. Unlike the case of shrinking Si-ND thickness, the case of shrinking Si-ND diameter simultaneously increased the optical absorption coefficient and the optical bandgap energy. The optical absorption coefficient became higher due to the decrease in the center-to-center distance of NDs to enhance wavefunction coupling. This means that our 6 nm diameter Si-ND structure can satisfy the strict requirements of optical bandgap energy control and high absorption coefficient for achieving realistic Si quantum dot solar cells.

15.
Neuroradiology ; 54(1): 13-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21331600

RESUMEN

INTRODUCTION: Rarely in the anterior circulation, an anastomosis of the carotid and anterior cerebral arteries occurs when an anomalous branch arises from the ophthalmic segment of the internal carotid artery and anastomoses with the A1-A2 junction of the anterior communicating artery. Right-side predominance is known. To our knowledge, the incidence of carotid-anterior cerebral artery anastomosis has not been reported, so we researched cases in our institution records to determine incidence and investigated characteristic features of the condition on magnetic resonance (MR) angiography. METHODS: To isolate such cases, we retrospectively reviewed cranial MR angiographic images of 3,491 consecutive patients in our institution. RESULTS: We found three cases with carotid-anterior cerebral artery anastomosis (two men, one woman), representing an incidence of 0.086%. The anastomosis was on the right in all three cases. A normal A1 segment of the anterior cerebral artery (ACA) was present in two cases but could not be identified in the remaining case on MR angiographic images that included source images. Two of the three patients demonstrated associated arterial variations in their carotid systems. CONCLUSIONS: On MR angiography, we observed a 0.086% incidence of carotid-anterior cerebral artery anastomosis in our institution and reaffirmed the right-side predominance of this anomaly. We found a high frequency of other associated arterial variations in the carotid system.


Asunto(s)
Arteria Cerebral Anterior/anomalías , Arterias Carótidas/anomalías , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico , Angiografía por Resonancia Magnética/métodos , Adulto , Anciano , Femenino , Hospitales Universitarios , Humanos , Masculino , Estudios Retrospectivos
16.
Neuroradiology ; 54(1): 19-23, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21340577

RESUMEN

INTRODUCTION: The craniovertebral junction is clinically important. The vertebral artery (VA) in its several variations runs within this area. We report the prevalence of these VA variations on magnetic resonance angiography (MRA). METHODS: We retrospectively reviewed MRA images, obtained using two 1.5-T imagers, of 2,739 patients, and paid special attention to the course and branching of the VA at the level of the C1-2 vertebral bodies. RESULTS: There were three types of VA variation at the C1-2 level: (1) persistent first intersegmental artery (FIA), (2) VA fenestration, and (3) posterior inferior cerebellar artery (PICA) originating from the C1/2 level. The overall prevalence of these three variations was 5.0%. There was no laterality in frequency, but we found female predominance (P < 0.05). We most frequently observed the persistent FIA (3.2%), which was sometimes bilateral. We found VA fenestration (0.9%) and PICA of C1/2 origin (1.1%) with almost equal frequency. Two PICAs of C1/2 origin had no normal VA branch. CONCLUSIONS: We frequently observed VA variations at the C1-2 level and with female predominance. The persistent FIA was most prevalent and sometimes seen bilaterally. Preoperative identification of these variations in VA is necessary to avoid complications during surgery at the craniovertebral junction.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico , Vértebras Cervicales/irrigación sanguínea , Angiografía por Resonancia Magnética/métodos , Arteria Vertebral/anomalías , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Malformaciones Vasculares del Sistema Nervioso Central/epidemiología , Distribución de Chi-Cuadrado , Niño , Preescolar , Femenino , Humanos , Lactante , Japón/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Factores Sexuales
17.
Neuroradiology ; 54(5): 445-50, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21732084

RESUMEN

INTRODUCTION: Fenestrations of cerebral arteries are most common in the vertebrobasilar (VB) system, and magnetic resonance (MR) angiographic studies of these variations are sparse. METHODS: We retrospectively reviewed MR angiographic images of 3,327 patients; images were obtained using two 1.5-T imagers and picked up fenestrations of the intracranial vertebral artery (VA), VB junction, and basilar artery (BA) for evaluation. RESULTS: In 92 patients, we found 93 fenestrations (2.80%), which included 18 of the intracranial VA (0.54% prevalence), 6 of the VB junction (0.18%), and 69 of the BA (2.07%). Most VA fenestrations were large, and the posterior inferior cerebellar artery arose from the fenestrated segment in 10 patients (56%). Fenestrations of the VB junction were small and triangular. Sixty-five (94%) of the 69 BA fenestrations were located at the proximal segment and had small slit-like configurations. The anterior inferior cerebellar artery arose from the fenestrated segment in 27 patients (37%). We found 18 cerebral aneurysms in 16 (17%) of the 92 patients with fenestration but detected only one aneurysm at the fenestration. CONCLUSION: The overall prevalence of fenestrations of the intracranial VB system was 2.77%. We found associated cerebral aneurysms relatively frequently but rarely at the fenestration.


Asunto(s)
Arteria Basilar/anomalías , Aneurisma Intracraneal/diagnóstico , Angiografía por Resonancia Magnética/métodos , Arteria Vertebral/anomalías , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos
18.
Surg Radiol Anat ; 34(5): 401-4, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22271164

RESUMEN

INTRODUCTION: Duplicate origin of the middle cerebral artery (MCA) is rare and has been misdiagnosed or confused as fenestration of the proximal M1 segment of the MCA. The condition is not a true fenestration and occurs when two MCA branches arise separately from the terminal segment of the internal carotid artery, and fuse to form an arterial ring. We researched our institutional records to determine the prevalence of such cases and investigated its characteristic features on magnetic resonance (MR) angiography. METHODS: To isolate these cases, we retrospectively reviewed cranial MR angiographic images of 3,491 patients obtained on either of two 1.5-tesla scanners at our institution from April 1, 2007 through December 31, 2009. RESULTS: We found four cases of duplicate origin of the MCA, two cases each on the right and the left (3 men, one woman), representing a prevalence of 0.11%. All four arterial rings were small and mimicked fenestration of the proximal M1 segment. During the same period, we found three MCA fenestrations, two at the proximal M1 segment and one at the middle M1 segment. Total prevalence of duplicate origin and fenestration was 0.20%. CONCLUSIONS: In our institution, we observed 0.11% prevalence of duplicate origin of the MCA on MR angiography, and all were small and mimicked fenestration. Clinically, an important difference between duplicate origin and fenestration of the MCA is the potential collateral circulation available from the inferior branch in the case of saddle embolism occlusion of only the superior branch when there is duplicate origin of the MCA.


Asunto(s)
Angiografía por Resonancia Magnética , Arteria Cerebral Media/anomalías , Adulto , Angiografía Cerebral , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
19.
Surg Radiol Anat ; 34(3): 271-6, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21739246

RESUMEN

INTRODUCTION: A persistent trigeminal artery (PTA) is the most common carotid-vertebrobasilar anastomosis. A cerebellar artery that arises from the precavernous segment of the internal carotid artery (ICA) without connecting to the basilar artery is regarded as a PTA variant. Our study aimed to determine the incidence of PTA and its variants and classify them based on magnetic resonance (MR) angiography. METHODS: We retrospectively reviewed cranial images of 3,626 patients who underwent MR angiography in our institution from April 1, 2007 through December 31, 2009. We ultimately reviewed and analyzed images of 3,491 patients (2,066 men, 1,425 women) after excluding 135 with unilateral or bilateral ICA occlusion or suboptimal image quality. RESULTS: We found 12 cases of PTA (7 men, 5 women; right 4, left 8; incidence; 0.34%) and 6 of PTA variants (3 men, 3 women; right 3, left 3; incidence; 0.17%). 11 of the 12 PTAs were lateral type; 1 was medial. In two of the lateral-type cases, the superior cerebellar artery (SCA) arose from the PTA. Among the six variants, the anterior inferior cerebellar artery (AICA) arose in five and the posterior inferior cerebellar artery (PICA), in one. CONCLUSIONS: On MR angiography, the incidence of PTA was 0.34% and of PTA variants, 0.17%. Left PTA was twice as frequent as right PTA, but with no statistical significance. Medial-type PTA was extremely rare. AICA arose in most PTA variants. Rarely, a lateral-type PTA gave rise to the cerebellar artery.


Asunto(s)
Arterias Carótidas/anatomía & histología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Arterias Carótidas/diagnóstico por imagen , Femenino , Humanos , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Radiografía , Estudios Retrospectivos , Adulto Joven
20.
Jpn J Radiol ; 40(4): 385-395, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34750737

RESUMEN

PURPOSE: To generate a new discrimination method to distinguish between malignant mesenchymal tumors of the uterus and T2-weighted hyperintense leiomyoma based on magnetic resonance imaging findings and clinical features. MATERIALS AND METHODS: Data from 32 tumors of 32 patients with malignant mesenchymal tumors of the uterus and from 34 tumors of 30 patients with T2-weighted hyperintense leiomyoma were analyzed. Clinical parameters, qualitative magnetic resonance imaging features, including computed diffusion-weighted imaging, and quantitative characteristics of magnetic resonance imaging of these two tumor types were compared. Predictive values for malignant mesenchymal tumors of the uterus were calculated using variant discriminant analysis. RESULTS: The T1 bright area on qualitative assessment and mean apparent diffusion coefficient value on quantitative assessment yielded the most independent magnetic resonance imaging differentiators of malignant mesenchymal tumors of the uterus and T2-weighted hyperintense leiomyoma. The classification accuracy of the variant discriminant analysis based on three selected findings, i.e., a T1 bright area, computed diffusion-weighted imaging with a b-value of 2000s/mm2 (cDWI2000), and T2-hypointense bands, was 84.8% (56/66), indicating high accuracy. CONCLUSIONS: Variant discriminant analysis using the T1 bright area, cDWI2000, and T2-hypointense bands yielded high accuracy for differentiating between malignant mesenchymal tumors of the uterus and T2-weighted hyperintense leiomyoma.


Asunto(s)
Leiomioma , Neoplasias Uterinas , Diagnóstico Diferencial , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Leiomioma/diagnóstico por imagen , Leiomioma/patología , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Neoplasias Uterinas/diagnóstico por imagen , Neoplasias Uterinas/patología , Útero/diagnóstico por imagen , Útero/patología
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