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1.
Br J Clin Pharmacol ; 90(2): 582-587, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37897050

RESUMO

AIMS: This study aimed to evaluate the predictive performance of previously constructed cefazolin pharmacokinetic models and determine whether cefazolin administration via the target-controlled infusion (TCI) method may be possible in clinical practice. METHODS: Twenty-five gastrectomy patients receiving cefazolin as a prophylactic antibiotic were enrolled. Two grams of cefazolin was dissolved in 50 mL of normal saline to give a concentration of 40 mg mL-1 . Before skin incision, cefazolin was administered using a TCI syringe pump, and its administration continued until the end of surgery. The target total plasma concentration was set to 100 µg mL-1 . Total and unbound plasma concentrations of cefazolin were measured in three arterial blood samples collected at 30, 60 and 120 min after the start of cefazolin administration. The predictive performance of the TCI system was evaluated using four measures: inaccuracy, divergence, bias and wobble. RESULTS: Total (n = 75) and unbound (n = 75) plasma concentration measurements from 25 patients were included in the analysis. The pooled median (95% confidence interval) biases and inaccuracies were 6.3 (4.0-8.5) and 10.5 (8.6-12.4) for the total concentration model and -10.3 (-16.8 to -3.7) and 22.4 (18.2-26.7) for the unbound concentration model, respectively. All unbound concentrations were above 10 µg mL-1 . CONCLUSION: Administration of cefazolin by the TCI method showed a clinically acceptable performance. Applying the TCI method by setting the total concentration as the target concentration rather than the unbound concentration is effective in maintaining a constant target concentration of cefazolin.


Assuntos
Antibacterianos , Cefazolina , Humanos , Antibioticoprofilaxia/métodos
2.
Phys Chem Chem Phys ; 24(26): 15718-15725, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35730195

RESUMO

Stable open- and closed-shell Pd(II) and Cu(II) complexes of hexaethyl tripyrrin-1,14-dione (TD1) produce triplet, doublet or singlet states depending on the metal center and the redox state of the ligand. Pd(II) and Cu(II) form neutral TD1 complexes featuring ligand-based radicals, thus resulting in doublet and triplet states, respectively. The reversible one-electron oxidation of the complexes removes an unpaired electron from the ligand, generating singlet and doublet states. The optical properties and time-resolved dynamics of these systems are studied here using steady-state and ultrafast transient absorption (pump-probe) measurements. Fast relaxation with recovery of the ground state in tens of picoseconds is observed for the copper neutral radical and oxidized complexes as well as for the palladium neutral radical complex. Significantly longer timescales are observed for the oxidized palladium complex. The ability to tune the overall spin state of the complexes through their stable open-shell configurations as well as the reversible redox activity of the tripyrrolic systems makes them particularly interesting for catalytic applications as well as exploring magnetism and conductivity properties.

3.
Eur Radiol ; 30(4): 2152-2160, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31844961

RESUMO

OBJECTIVE: To assess the diagnostic accuracy of 256-row multislice computed tomographic angiography (CTA) compared with three-dimensional rotational angiography (3DRA) in the postoperative evaluation of cerebral aneurysms treated with titanium clips. METHODS: A total of 128 patients (42 men, 86 women; mean age, 57.6 years) with 143 cerebral aneurysms treated using titanium clips underwent both CTA and 3DRA. Two reviewers retrospectively evaluated the following parameters on CTA and 3DRA: (1) residual/recurrent aneurysm (absent or present), (2) patency of parent artery (patent or occluded/severe stenotic (> 70%)), and (3) patency of adjacent branch (patent or occluded/absent). RESULTS: A total of 24 residual/recurrent aneurysms were detected by 3DRA. The sensitivity, specificity, and accuracy of CTA for the detection of residual/recurrent aneurysms were 83.3%, 100%, and 97.2% for reviewer 1 and 79.2%, 100%, and 96.5% for reviewer 2, respectively. The sensitivity, specificity, and accuracy of CTA for the evaluation of patency of parent artery were 100%, 100%, and 100%, respectively, for both reviewers. The sensitivity, specificity, and accuracy of CTA for evaluation of the patency of adjacent branch were 85.1%, 100%, and 92.3% for reviewer 1 and 82.4%, 100%, and 90.9% for reviewer 2, respectively. CONCLUSION: A 256-row multislice CTA is a valuable non-invasive tool for assessment of cerebral aneurysms treated with titanium clips. KEY POINTS: • A 256-row multislice CTA is an accurate imaging technique for the postoperative assessment of cerebral aneurysms treated with titanium clips. • Sensitivity of CTA for the detection of residual/recurrent aneurysms was 79-83% compared with 3DRA. • CTA is still limited in detecting residual/recurrent aneurysms of < 2 mm and small adjacent branches.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/diagnóstico , Tomografia Computadorizada Multidetectores/métodos , Titânio , Procedimentos Cirúrgicos Vasculares/instrumentação , Adulto , Angiografia Cerebral/métodos , Feminino , Humanos , Aneurisma Intracraniano/cirurgia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Período Pré-Operatório , Reprodutibilidade dos Testes , Estudos Retrospectivos , Instrumentos Cirúrgicos
4.
Br J Neurosurg ; 33(5): 490-494, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31092005

RESUMO

Purpose: To describe our experiences with a fully equipped high-end digital subtraction angiography (DSA) system within a hybrid operating room (OR). Material and methods: A single-plane DSA system with 3-dimensional rotational angiography (3DRA), cone-beam computed tomography, and real-time navigation software was used in our hybrid OR. Between April 2014 and January 2018, 191 sessions of neurovascular procedures were performed in our hybrid OR. After the retrospective review of all cases, the procedures were categorised into five subcategorical procedures according to the dominance of surgical and/or endovascular procedures: intraoperative angiographic evaluation, combined endovascular and surgical procedure, complementary rescue procedure during intervention and surgery, surgical approach for interventional procedure, and frameless stereotaxic operation. Results: Intraoperative angiography revealed unsatisfactory clipping of intracranial aneurysms in 6 (13.6%) patients and remnant AVMs in 1 (16.7%) patient, which were determined as complete surgical outcome via indocyanine green videoangiography. Four cases of blood blister aneurysms and a ruptured posterior inferior cerebellar artery aneurysm were treated using bypass surgery and endovascular trapping. Eight cases of ruptured aneurysm with intracranial haemorrhage (ICH) were treated by partial embolisation and surgical clipping. Two (5.4%) of the 37 cases of pre-mature rupture during clipping were secured by endovascular coil embolisation. In 1 (0.8%) complicated case of 103 intra-arterial (IA) thrombectomy procedures, emergency surgical embolectomy with bypass surgery was performed. Direct puncture of the common carotid artery or vertebral artery was performed to achieve interventional access to treat aneurysm or recanalise vessel occlusions in 7 cases. In 27 cases of ICH, frameless stereotaxic haematoma aspiration was performed using XperGuide® system. All procedures were performed in single sessions without any procedural complications. Conclusion: Hybrid OR with a fully equipped DSA system could provide safe and precise treatment for neurovascular diseases. Hybrid procedures for neurovascular diseases in hybrid OR are a promising new trend.


Assuntos
Transtornos Cerebrovasculares/cirurgia , Procedimentos Endovasculares/métodos , Procedimentos Neurocirúrgicos/métodos , Salas Cirúrgicas/organização & administração , Adulto , Aneurisma Roto/cirurgia , Angiografia Digital , Transtornos Cerebrovasculares/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Embolização Terapêutica , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Hemorragias Intracranianas/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Técnicas Estereotáxicas , Trombectomia
5.
Nano Lett ; 17(2): 762-771, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28045274

RESUMO

Femtosecond two-dimensional Fourier transform spectroscopy is used to determine the static bandgap inhomogeneity of a colloidal quantum dot ensemble. The excited states of quantum dots absorb light, so their absorptive two-dimensional (2D) spectra will typically have positive and negative peaks. It is shown that the absorption bandgap inhomogeneity is robustly determined by the slope of the nodal line separating positive and negative peaks in the 2D spectrum around the bandgap transition; this nodal line slope is independent of excited state parameters not known from the absorption and emission spectra. The absorption bandgap inhomogeneity is compared to a size and shape distribution determined by electron microscopy. The electron microscopy images are analyzed using new 2D histograms that correlate major and minor image projections to reveal elongated nanocrystals, a conclusion supported by grazing incidence small-angle X-ray scattering and high-resolution transmission electron microscopy. The absorption bandgap inhomogeneity quantitatively agrees with the bandgap variations calculated from the size and shape distribution, placing upper bounds on any surface contributions.

6.
Neuroradiology ; 59(5): 491-497, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28343249

RESUMO

PURPOSE: Accurate and reliable measurement of aneurysm size is important for treatment planning. The purpose of this study was to determine intraobserver and interobserver variability of CTA and MRA for measurement of the size of cerebral aneurysms. METHODS: Thirty patients with 33 unruptured cerebral aneurysms (saccular, >3 mm in their maximal dimension, with no daughter sacs or lobulations) who underwent 256-row multislice CTA, 3-D TOF MRA at 3.0T, and 3D rotational angiography (3DRA) were retrospectively analyzed. Three independent observers measured the neck, height, and width of the aneurysms using the CTA and MRA images. Intraobserver and interobserver variability of CTA and MRA measurements was evaluated using the standardized difference and intraclass correlation coefficient, with 3DRA measurements as the reference standard. In addition, the mean values of the measurements using CTA and MRA were compared with those using 3DRA. RESULTS: The overall intraobserver and interobserver standardized differences in CTA/MRA were 12.83-15.92%/13.48-17.45% and 14.08-17.00%/12.08-17.67%, respectively. The overall intraobserver and interobserver intraclass correlation coefficients of CTA/MRA were 0.88-0.98/0.84-0.96 and 0.86-0.98/0.85-0.95, respectively. Compared to the height and width measurements, measurements of the neck dimensions showed higher intraobserver and interobserver variability. The sizes of the cerebral aneurysms measured by CTA and MRA were 1.13-9.26 and 5.20-9.67% larger than those measured by 3DRA, respectively; however, these differences were not statistically significant. CONCLUSION: There were no noticeable differences between intraobserver and interobserver variability for both CTA- and MRA-based measurements of the size of cerebral aneurysms.


Assuntos
Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Aneurisma Intracraniano/diagnóstico por imagem , Angiografia por Ressonância Magnética , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Imageamento Tridimensional , Iopamidol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos
7.
Opt Lett ; 39(3): 513-6, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24487853

RESUMO

An intrinsically phase-stable Sagnac interferometer is introduced for optimized interferometric detection in partially collinear two-dimensional (2D) spectroscopy. With a pump-pulse pair from an actively stabilized Mach-Zehnder interferometer, the Sagnac scheme is demonstrated in broadband, short-wave IR (1-2 µm), 2D electronic spectroscopy of IR-26 dye.

8.
Neuroradiology ; 56(11): 917-23, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25103608

RESUMO

INTRODUCTION: Infundibular dilation (ID) and aneurysm at the internal carotid artery (ICA)-posterior communicating artery (PComA) junction can be difficult to distinguish but may differ in clinical significance. The aim of this study was to evaluate the utility of CT angiography (CTA) in differentially diagnosing IDs and small unruptured aneurysms at the ICA-PComA junction. METHODS: This retrospective study comprised 88 patients diagnosed with 107 protrusions (70 IDs and 37 aneurysms <5 mm; 19 bilateral lesions) at the ICA-PComA junction who underwent both CTA and digital subtraction angiography (DSA). Two neuroradiologists independently reviewed CTA and DSA images according to these criteria: (a) size (maximum dimension <3 or ≥3 mm), (b) shape (triangular or round/oval/irregular), (c) aneurysmal neck (absent or present), (d) horizontal direction (posteriomedial or posteriolateral), and (e) PComA origin (apex, no PComA, or base). The intermodality (between CTA and DSA) and interobserver (between the two readers) agreement were determined for each finding. We also evaluated the sensitivity and specificity of CTA for distinguishing ID and aneurysm, using DSA as the reference standard. RESULTS: The mean κ values of intermodality agreement for the size, shape, aneurysmal neck, horizontal direction, and PComA origin were 0.88, 0.87, 0.84, 0.71, and 0.56, respectively. All interobserver agreements of CTA and DSA were excellent. The sensitivity, specificity, and accuracy of CTA for differentiating aneurysms from IDs were 94.6, 100, and 98.0 %, respectively. CONCLUSION: CTA may be a useful noninvasive modality for differential diagnosis of ID and aneurysm at the ICA-PComA junction.


Assuntos
Doenças das Artérias Carótidas/diagnóstico por imagem , Artéria Carótida Interna , Angiografia Cerebral , Aneurisma Intracraniano/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Valor Preditivo dos Testes , Estudos Retrospectivos , Adulto Jovem
9.
Anal Chem ; 85(11): 5514-21, 2013 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-23663173

RESUMO

Absolute molecular number concentration and extinction coefficient are simultaneously determined from linear and nonlinear spectroscopic measurements. This method is based on measurements of absolute femtosecond pump-probe signals. Accounting for pulse propagation, we present a closed form expression for molecular number concentration in terms of absorbance, fluorescence, absolute pump-probe signal, and laser pulse parameters (pulse energy, spectrum, and spatial intensity profile); all quantities are measured optically. As in gravimetric and coulometric determinations of concentration, no standard samples are needed for calibration. The extinction coefficient can then be determined from the absorbance spectrum and the concentration. For fluorescein in basic methanol, the optically determined molar concentrations and extinction coefficients match gravimetric determinations to within 10% for concentrations from 0.032 to 0.540 mM, corresponding to absorbance from 0.06 to 1. In principle, this photonumeric method is extensible to transient chemical species for which other methods are not available.


Assuntos
Fluoresceína/análise , Fluoresceína/química , Lasers , Espectrometria de Fluorescência/métodos
10.
Eur Radiol ; 23(6): 1443-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23263605

RESUMO

OBJECTIVES: To retrospectively investigate the prevalence and characteristics of intracranial vascular lesions in patients with acute severe headache with the use of CT angiography (CTA). METHODS: We systematically searched for neurologically intact patients with acute severe headache and normal unenhanced head CT. The study group consisted of 512 patients; 251 male; mean age 46.2 ± 12.4 years. All patients underwent CTA between 1 day and 2 months after the headache attack. CTA images were interpreted by two experienced neuroradiologists for the presence of vascular lesions. RESULTS: Thirty-four (6.6 %) of the 512 patients had intracranial vascular lesions on CTA, including 33 aneurysms (2 patients had 2 aneurysms each), 2 moyamoya disease and 1 arterial dissection. No gender- or age-related differences were found. Aneurysms arose most commonly on the internal carotid artery (n = 12), followed by the anterior communicating artery (n = 7), and the middle cerebral artery (n = 7). Maximal diameters ranged from 2.0 to 13.1 mm (mean, 3.9 ± 2.6 mm). CONCLUSIONS: CTA is a feasible tool for diagnosing intracranial vascular lesions in patients with acute severe headache. The prevalence of vascular lesions in our series was 6.6 %, which is higher than that predicted in the general population. KEY POINTS: • Unruptured cerebral aneurysms may be a cause of acute severe headache • CTA assesses intracranial vascular lesions in patients with acute severe headache • The prevalence of vascular lesions in our series of patients was 6.6 %


Assuntos
Angiografia Cerebral/métodos , Cefaleia/diagnóstico , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/diagnóstico por imagem , Angiografia Digital/métodos , Artéria Carótida Interna/patologia , Feminino , Cefaleia/diagnóstico por imagem , Cefaleia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/patologia , Doença de Moyamoya/diagnóstico , Doença de Moyamoya/diagnóstico por imagem , Prevalência , Estudos Retrospectivos , Adulto Jovem
11.
J Phys Chem A ; 117(29): 6332-45, 2013 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-23713582

RESUMO

The absolute femtosecond pump-probe signal strength of deprotonated fluorescein in basic methanol is measured. Calculations of the absolute pump-probe signal based on the steady-state absorption and emission spectrum that use only independently measured experimental parameters are carried out. The calculation of the pump-probe signal strength assumes the pump and probe fields are both weak and includes the following factors: the transverse spatial profile of the laser beams; the pulse spectra; attenuation of the propagating pulses with depth in the sample; the anisotropic transition probability for polarized light; and time-dependent electronic population relaxation. After vibrational and solvent relaxation are complete, the calculation matches the measurement to within 10% error without any adjustable parameters. This demonstrates quantitative measurement of absolute excited state population.

12.
Acta Radiol ; 52(8): 889-93, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21828003

RESUMO

BACKGROUND: Computed tomography angiography (CTA) is increasingly used for non-invasive imaging of the cerebrovascular diseases. PURPOSE: To evaluate the accuracy of CTA in the assessment of the variation of the segment calibers of the circle of Willis. MATERIAL AND METHODS: One hundred and 17 patients with acute SAH (51 men and 66 women, mean age 50.9 years) who underwent CTA using a 16 detector-row CT scanner and DSA were evaluated retrospectively. The CTA and DSA studies were performed within 24 h after the onset of symptoms and within 24 h of each other. A total of 819 arterial segments (A-comA, right and left A1 segment, right and left P-com A, and right and left P1 segment) of the circle of Willis were determined to be aplastic (grade 1), hypoplastic (grade 2), or normal-sized (grade 3) by blinded observers evaluating CTA volume-rendered images. The CTA results were then compared with findings on the corresponding DSA images (reference standard). RESULTS: The overall agreement between CTA and DSA was 92.4%. We had 62 (7.6%) cases of disagreement (58 cases of under-estimation and four cases of over-estimation by CTA) between tow modalities. The sensitivity and specificity of CTA in the detection of aplastic and normal-sized segments were more than 90%. In contrast, subgroup analysis of the hypoplastic segments showed a sensitivity of 52.6% and a specificity of 98.2%. CONCLUSION: CTA is highly accurate in the assessment of anatomical variations of the circle of Willis; however, its sensitivity is limited in depicting hypoplastic segments.


Assuntos
Angiografia Digital/métodos , Angiografia Cerebral/métodos , Círculo Arterial do Cérebro/diagnóstico por imagem , Hemorragia Subaracnóidea/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Feminino , Humanos , Iohexol , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
Nano Lett ; 10(7): 2498-505, 2010 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-20550102

RESUMO

Hot electronic dynamics in lead sulfide nanocrystals is interrogated by degenerate pump-probe spectroscopy with 20-25 fs pulses over a broad frequency range around three times the nanocrystal band gap. For each nanocrystal diameter, an initial reduction in absorption is seen only at the peak of the quantum confined E1 transition, while increased absorption is seen at all other wavelengths. The signals from the nanocrystals are approximately 300 times weaker than expected for a two-level system with the same absorbance and molar extinction coefficient and are weaker near time zero. These results appear to be inconsistent with quantum confinement of the initially excited high energy states. Arguments based on carrier scattering length, the wave packet size supported by the band structure, and effective mass are advanced to support the hypothesis that, for many direct-gap semiconductor quantum dots, the carrier dynamics at three times the band gap is localized on the 1-2 nm length scale and essentially bulklike except for frequent collisions with the surface.

14.
J Neuroimaging ; 31(3): 532-540, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33848017

RESUMO

BACKGROUND AND PURPOSE: We aimed to assess the accuracy of magnetic resonance angiography (MRA) in the differentiation of small aneurysms versus infundibular dilations (IDs) at the internal carotid artery-posterior communicating artery (ICA-PComA) junction, emphasizing the role of MRA axial source images. METHODS: This retrospective study consisted of 83 focal arterial protrusions at ICA-PComA junction in 76 patients who underwent both MRA and digital subtraction angiography (DSA)/3-dimensional rotational angiography (3DRA). The diagnostic performance of MRA for differential diagnosis of aneurysm from ID was calculated using DSA/3DRA interpretation as the standard of reference. In addition, long-axis diameter, short-axis diameter, long-axis diameter/short-axis diameter (L/S) ratio, and angle of lesion (angle of the long-axis of lesion with respect to the x-axis) measured on MRA source images were compared between aneurysms and IDs. RESULTS: Sensitivity, specificity, and accuracy of MRA for distinguishing aneurysms from IDs were 74.4% (57.9-87.0%) to 76.9% (60.7-88.9%), 93.2% (81.3-98.6%) to 95.5% (84.5-99.4%), and 85.5% (76.1-92.3%), respectively. Significant differences were found for the long-axis diameter (P < .001), short-axis diameter (P < .001), L/S ratio (P < .05), and angle of the lesion (P < .001) on MRA axial source images between aneurysms and IDs. The angle of the lesion had the highest discriminatory ability (area under the curve = .966 [.902-.994]) to differentiate aneurysms from IDs. An angle of lesion >60° was 89.7% (75.8-97.1%) sensitive and 100% (92.0-100.0%) specific for diagnosis of aneurysm. CONCLUSIONS: MRA is a useful imaging modality for distinguishing between aneurysm and ID at the ICA-PComA junction. Furthermore, geometric parameters on MRA axial source images can provide added value in their differentiation.


Assuntos
Angiografia Digital/métodos , Artéria Carótida Interna/diagnóstico por imagem , Dilatação Patológica/diagnóstico , Aneurisma Intracraniano/diagnóstico , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Dilatação , Dilatação Patológica/diagnóstico por imagem , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
Childs Nerv Syst ; 26(1): 117-20, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19629493

RESUMO

INTRODUCTION: Pseudoaneurysm of the superficial temporal artery (STA) is usually caused by head or facial injury and is rarely reported in children. It is frequently discovered as a pulsatile cystic mass in the temple, and its diagnosis can be made with ultrasound or computerized tomography angiogram (CTA). Treatment modalities consist of surgical excision and endovascular embolization. CASE REPORT: A 14-year-old boy presented with a pulsatile, cystic, and painless mass in the left anterior temporal region, developed 6 weeks after head injury from a traffic accident. The mass was 15 mm in diameter and compressible, and disappeared after manual compression of the proximal STA. Bruit was audible over the mass with a stethoscope. CTA showed a pseudoaneurysm of the anterior division of the left STA. The mass was resected with ligation of the proximal and distal ends of the STA. CONCLUSION: A pseudoaneurysm of the STA should be suspected in a child presented with a pulsatile, cystic mass in the temple, developed after head injury. It can be easily diagnosed with history and physical examination with the aid of imaging modalities such as Doppler ultrasonography and CTA. Pseudoaneurysms are usually successfully treated with excision.


Assuntos
Falso Aneurisma/diagnóstico , Falso Aneurisma/cirurgia , Doenças Arteriais Cerebrais/diagnóstico , Doenças Arteriais Cerebrais/cirurgia , Traumatismos Craniocerebrais/complicações , Artérias Temporais/cirurgia , Acidentes de Trânsito , Adolescente , Falso Aneurisma/etiologia , Angiografia Cerebral , Doenças Arteriais Cerebrais/etiologia , Diagnóstico Diferencial , Humanos , Imageamento Tridimensional , Masculino , Artérias Temporais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
16.
J Phys Chem A ; 113(47): 13287-99, 2009 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-19780599

RESUMO

Four-level two-dimensional (2D) Fourier transform relaxation spectra are simulated with response functions for a chromophore pair in the exponential relaxation (optical Bloch model) limit. The parameters in this study are chosen to model coupled carbonyl stretching vibrations. As long as coherence persists, every peak in the real 2D spectra has a partially mixed absorptive/dispersive ("phase-twisted") shape because the nonlinear signals are not symmetric with respect to interchange of the first two pulses. This asymmetry in 2D relaxation spectra arises from coherence between singly excited states and a red shift of the doubly excited state. Coherence between the singly excited states causes oscillation of the 2D spectra and the associated spectrally resolved pump-probe (SRPP) transients at the quantum beat frequency. Projecting the phase-twisted nature of the 2D peaks onto the detection frequency axis, the SRPP peaks are also asymmetric about their maximum when not at maximum or minimum amplitude. Three-dimensional Fourier transform (3DFT) methods are used to simulate absorption/dispersion and beam geometry distortions of the multilevel 2D spectra with cross peaks. The distortions can be understood by consideration of their effects on individual coherence pathways that contribute to peaks in the 2D spectra. The beam geometry distortion explains some unequal cross peak amplitudes previously observed experimentally by Khalil et al. (J. Chem. Phys. 2004, 121, 362). A representation of 2D spectra that reduces beam geometry distortion is presented. If the transformation to correct for beam geometry distortion is combined with the transformations that correct absorptive/dispersive propagation distortions (J. Chem. Phys. 2007, 126, 044511), the recovered 2D spectrum matches the ideal 2D spectrum after all coherence is destroyed. In the presence of coherence, the new representation reduces the error in the distorted 2D spectrum by a factor of 4 for practical 2D-IR experimental conditions.

17.
J Phys Chem B ; 123(26): 5524-5535, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31177778

RESUMO

The optical properties and ultrafast dynamics of hexaethyl tripyrrin-1,14-dione (H3TD1) are tuned by hydrogen-bonding interactions between the solute and the solvent. In solvents with low hydrogen-bonding affinity, H3TD1 preferentially forms hydrogen-bonded dimers, whereas in solvents that can either donate or accept hydrogen bonds H3TD1 is present as a monomer. The distinction between dimer and monomer determines the dynamics of the system, with faster internal conversion observed in the dimer form. The ultrafast dynamics were characterized using time-correlated single photon counting, fluorescence upconversion, and transient absorption measurements. The time-resolved dynamics of both the monomer and dimer in solution were modeled using a Pauli master equation treatment for a three level system. The solvent-dependent optical properties were measured using steady-state absorption and fluorescence. This data was then used to calculate the quantum yield and extinction coefficients.

18.
J Korean Neurosurg Soc ; 62(1): 35-45, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30630294

RESUMO

OBJECTIVE: To describe our experiences with a fully equipped high-end digital subtraction angiography (DSA) system within a hybrid operating room (OR). METHODS: A single-plane DSA system with 3-dimensional rotational angiography, cone-beam computed tomography (CBCT), and real-time navigation software was used in our hybrid OR. Between April 2014 and January 2018, 191 sessions of cerebrovascular procedures were performed in our hybrid OR. After the retrospective review of all cases, the procedures were categorized into three subcategorical procedures : combined endovascular and surgical procedure, complementary rescue procedure during intervention and surgery, and frameless stereotaxic operation. RESULTS: Forty-nine of 191 procedures were performed using hybrid techniques. Four cases of blood blister aneurysms and a ruptured posterior inferior cerebellar artery aneurysm were treated using bypass surgery and endovascular trapping. Eight cases of ruptured aneurysm with intracranial hemorrhage (ICH) were treated by partial embolization and surgical clipping. Six cases of ruptured arteriovenous malformation with ICH were treated by Onyx embolization of nidus and subsequent surgical removal of nidus and ICH. Two (5.4%) of the 37 cases of pre-mature rupture during clipping were secured by endovascular coil embolization. In one (0.8%) complicated case of 103 intra-arterial thrombectomy procedures, emergency surgical embolectomy with bypass surgery was performed. In 27 cases of ICH, frameless stereotaxic hematoma aspiration was performed using XperGuide® system (Philips Medical Systems, Best, the Netherlands). All procedures were performed in single sessions without any procedural complications. CONCLUSION: Hybrid OR with a fully equipped DSA system could provide precise and safe treatment strategies for cerebrovascular diseases. Especially, we could suggest a strategy to cope flexibly in complex lesions or unexpected situations in hybrid OR. CBCT with real-time navigation software could augment the usefulness of hybrid OR.

19.
J Neurointerv Surg ; 11(5): 528-532, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30538146

RESUMO

BACKGROUND AND PURPOSE: Alternative metrics (altmetrics), based on mentions in online media, is a new tool that can help to identify the most influential articles to diverse public audiences. This article aimed to determine the 100 most mentioned articles in the field of neurointervention and to analyze their characteristics. MATERIALS AND METHODS: We selected the 808 journals that were considered journals potentially publishing articles on neurointervention. We also selected articles using keywords. Using the Altmetric.com search tool, we identified the 101 most mentioned neurointervention articles based on the highest altmetric attention scores (AASs) within selected journals and articles. Each article was evaluated for several characteristics including AAS, number of citations, journal title, journal category, impact factor of the journal, year of publication, authorship, country, type of document, and topic. RESULTS: The AASs for the top 101 articles ranged from 1586 to 39. Stroke published the largest number of articles (19.8%) followed by the New England Journal of Medicine (17.8%). The majority of articles were published in multidisciplinary journals (38.6%), were published in 2017-2018 (43.6%), originated from the USA (54.5%), were original articles (66.3%), and dealt with intra-arterial thrombolysis or thrombectomy for acute ischemic stroke (58.4%). Tudor G Jovin was the most prolific author, authoring 18 of the most mentioned neurointervention articles CONCLUSIONS: This study presents a detailed list of the 101 most mentioned neurointervention articles in online media, thus providing useful information on the dissemination of neurointervention research to the general public.


Assuntos
Bibliometria , Neurocirurgia/estatística & dados numéricos , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Embolização Terapêutica , Internet , Fator de Impacto de Revistas , Publicações Periódicas como Assunto , Trombectomia
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