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1.
Clin Anat ; 30(1): 50-52, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27599380

RESUMO

Routine magnetic resonance imaging (MRI) of the skull and brain for diagnostic purposes sometimes reveals a wider tip of the frontal ventricular horn on one side and a wider tip of the temporal horn on the other. A search for 'alternate ventricular asymmetry' in Google Scholar, Medline and PubMed Central yielded no results, so the digital archive of the hospital was searched for such cases. A total of 5908 examinations were reviewed and 508 cases were found, comprising 6% of the neurological inpatients and 20% of the psychiatric inpatients (P = 0.001 by χ2 ). The >3-fold difference in the incidence of this particular ventricular asymmetry implies that it could suggest a psychiatric diagnosis. Clin. Anat. 30:50-52, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Ventrículos Cerebrais/patologia , Transtornos Mentais/patologia , Feminino , Humanos , Masculino
2.
Eur J Neurol ; 18(12): 1407-11, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21672089

RESUMO

BACKGROUND AND PURPOSE: As patients with abnormal baseline coagulation were excluded from the large randomized trials, the safety of intravenous thrombolysis after ischaemic stroke in this patient population remains controversial. METHODS: We assessed the risk of symptomatic intracerebral hemorrhage (SICH) after systemic thrombolysis in patients with elevated baseline international normalized ratios (INRs) (≥1.3) or activated partial thromboplastin times (aPTT) (>37 s) using a prospectively recorded database from 2006 to 2010. An intracerebral hemorrhage leading to a deterioration of ≥4 points on the National Institutes of Health Stroke scale (NIHSS) was classified as symptomatic. RESULTS: Amongst 688 patients (mean age, 72 years; median NIHSS, 11, median onset-to-treatment time, 135 min), 36 patients (5%) had an abnormal baseline coagulation. Twenty-nine of these patients had taken oral anticoagulants leading to elevated baseline INRs (median INR: 1.5; IQR 1.4-1.9), whereas seven patients had elevated aPTTs because of heparin therapy (n = 2), a coagulation disorder (n = 2), or for unknown reasons (n = 3). The rate of SICH did not differ significantly between patients with abnormal and normal baseline coagulation (4.4% vs. 0%; P = 0.6). Moreover, the in-hospital mortality was not significantly different between both treatment groups (8.3% in patients with abnormal baseline coagulation vs. 8.7% in patients with normal baseline coagulation, P = 1.0). CONCLUSIONS: The risk of SICH following intravenous thrombolysis after ischaemic stroke does not appear to be increased in patients with abnormal baseline coagulation.


Assuntos
Hemorragia Cerebral/etiologia , Fibrinolíticos/efeitos adversos , Transtornos Hemorrágicos/complicações , Coeficiente Internacional Normatizado , Tempo de Tromboplastina Parcial , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/efeitos adversos , Ativador de Plasminogênio Tecidual/efeitos adversos , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Hemorragia Cerebral/induzido quimicamente , Comorbidade , Diabetes Mellitus/epidemiologia , Dislipidemias/epidemiologia , Feminino , Fibrinolíticos/uso terapêutico , Transtornos Hemorrágicos/sangue , Transtornos Hemorrágicos/induzido quimicamente , Mortalidade Hospitalar , Humanos , Hipertensão/epidemiologia , Masculino , Estudos Prospectivos , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Fatores de Risco , Índice de Gravidade de Doença , Fumar/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Ativador de Plasminogênio Tecidual/uso terapêutico , Tomografia Computadorizada por Raios X
3.
AJNR Am J Neuroradiol ; 28(7): 1362-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17698541

RESUMO

BACKGROUND AND PURPOSE: Bone-subtraction techniques have been shown to enhance CT angiography (CTA) interpretation, but motion can lead to incomplete bone removal. The aim of this study was to evaluate 2 novel registration techniques to compensate for patient motion. MATERIALS AND METHODS: Fifty-four patients underwent bone-subtraction CTA (BSCTA) for the evaluation of the neck vessels with 64-section CT. We tested 3 different registration procedures: pure rigid registration (BSCTA), slab-based registration (SB-BSCTA), and a partially rigid registration (PR-BSCTA) approach. Subtraction quality for the assessment of different vascular segments was evaluated by 2 examiners in a blinded fashion. The Cohen kappa test was applied for interobserver variability, and the Wilcoxon signed rank test, for differences between the procedures. Motion between the corresponding datasets was measured and plotted against image-quality scores. RESULTS: Algorithms with motion compensation revealed higher image-quality scores (SB-BSCTA, mean 4.31; PR-BSCTA, mean 4.43) than pure rigid registration (BSCTA, mean 3.88). PR-BSCTA was rated superior to SB-BSCTA for the evaluation of the cervical internal and external carotid arteries (P<.001), whereas there was no significant difference for the other vessels (P=.157-.655). Both algorithms were clearly superior to pure rigid registration for all vessels except the basilar and ophthalmic artery. Interobserver agreement was high (kappa=0.46-0.98). CONCLUSION: Bone-subtraction algorithms with motion compensation provided higher image-quality scores than pure rigid registration methods, especially in cases with complex motion. PR-BSCTA was rated superior to SB-BSCTA in the visualization of the internal and external carotid arteries.


Assuntos
Artefatos , Osso e Ossos/diagnóstico por imagem , Angiografia Cerebral/métodos , Aumento da Imagem/métodos , Técnica de Subtração , Tomografia Computadorizada por Raios X/métodos , Cabeça/irrigação sanguínea , Cabeça/diagnóstico por imagem , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Movimento (Física) , Pescoço/irrigação sanguínea , Pescoço/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
AJNR Am J Neuroradiol ; 27(1): 55-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16418356

RESUMO

PURPOSE: CT angiography (CTA) has been established for detection and therapy planning of intracranial aneurysms. The analysis of aneurysms at the level of the skull base, however, remains difficult because bone prevents a free view. We report initial clinical results of an approach for automatic bone elimination from CTA data. MATERIAL AND METHODS: Before the bone-removal process 2 datasets are acquired: nonenhanced spiral CT with reduced dose and contrast-enhanced CTA. The software automatically registers the nonenhanced data onto the CTA data and selectively removes bone. Vascular structures, as well as brain tissue, remain visible. In this study, we investigated 27 patients with 29 aneurysms, 13 of which were located at the skull base. 3D volume-rendered images with and without bone removal were reviewed and compared with digital subtraction angiography by 2 radiologists in consensus. RESULTS: All supraclinoidal aneurysms were detected on 3D volume-rendered images of both CTA and bone-subtraction CT angiography (BSCTA). Four intracavernous and 3 paraclinoid aneurysms of the internal carotid artery were not visible or were only partially visible on conventional 3D CTA, whereas they could be optimally visualized with BSCTA. Bone removal was successful in all patients; the average additional time for postprocessing was 6.2 minutes. In 7 patients (26%), perfect bone removal without any artifacts was achieved. In most patients, some bone remnants were still present, though it did not disturb the 3D visualization of vascular structures. CONCLUSION: BSCTA allows robust and fast selective elimination of bony structures, thus ascertaining a better analysis of arteries at the level of the skull base. This is useful for both detection and therapy planning of intracranial aneurysms.


Assuntos
Angiografia Digital , Angiografia Cerebral , Aneurisma Intracraniano/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Artéria Carótida Interna/diagnóstico por imagem , Meios de Contraste , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Artéria Oftálmica/diagnóstico por imagem , Crânio , Tomografia Computadorizada Espiral
5.
Int J Angiol ; 25(5): e142-e144, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28031680

RESUMO

This article describes the aberrant course of the internal carotid artery (ICA) through the middle ear as an extremely rare vascular anomaly. On the basis of a case report, the findings of magnetic resonance imaging, computed tomography imaging, and especially color-coded duplex sonography are presented. The diagnosis of an aberrant ICA is important to avoid severe surgical complications of a retrotympanic mass as well as unnecessary diagnostic or therapeutic approaches in expectation of a stroke.

6.
Ophthalmologe ; 102(11): 1083-9, 2005 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-15889260

RESUMO

BACKGROUND: Tonic pupil (TP) is a common disorder of parasympathetic innervation. In contrast to textbook recommendations, cranial imaging is still being performed in most of the patients with TP. The intention of the present study is to show that cranial imaging is of no benefit. PATIENTS AND METHODS: The medical records of 33 patients with TP were analyzed retrospectively. All patients had undergone a complete ophthalmological, orthoptic, and neurological investigation. Cranial imaging was performed by computed tomography or magnetic resonance imaging. Serology tests were carried out in some of the patients. RESULTS: Diagnostic imaging provided no additional data revealing the underlying cause of TP. CONCLUSIONS: Cranial imaging in isolated tonic pupil is not helpful. Because of therapeutic implications, diagnostic evaluation can be recommended only in patients older than 50 years to exclude giant cell arteritis and syphilis.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Testes Sorológicos/métodos , Tomografia Computadorizada por Raios X/métodos , Pupila Tônica/diagnóstico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
Stroke ; 34(6): 1412-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12764232

RESUMO

BACKGROUND AND PURPOSE: Inflammation and hypercoagulability contribute to the development of acute cerebral ischemia. Both can be mediated by the CD40 system. This study investigated whether the CD40 system and related mediators are upregulated in patients with transient ischemic attack (TIA) or stroke. METHODS: Seventeen patients with TIA, 60 patients with complete stroke, and 15 control subjects were investigated. CD154 and P-selectin were analyzed on platelets and CD40 on monocytes during and 3 months after acute cerebral ischemia by double-label flow cytometry. Blood concentrations of soluble CD154 and monocyte chemoattractant protein-1 (MCP-1) were evaluated. RESULTS: Our main findings are as follows: (1) patients with acute cerebral ischemia showed a significant increase of CD154 on platelets and CD40 on monocytes compared with controls; (2) plasma levels of soluble CD154 were significantly higher in these patients; (3) these patients had significantly higher numbers of prothrombotic platelet-monocyte aggregates; (4) the chemoattractant MCP-1 was significantly elevated in cerebral ischemia; and (5) at 3 months' follow-up, upregulation of CD154 still persisted in patients with previous acute cerebral ischemia. CONCLUSIONS: Patients with acute cerebral ischemia show upregulation of the CD40 system, which might contribute to the known proinflammatory, proatherogenic, and prothrombotic milieu found in these patients.


Assuntos
Isquemia Encefálica/fisiopatologia , Antígenos CD40/metabolismo , Ligante de CD40/metabolismo , Doença Aguda , Biomarcadores/análise , Biomarcadores/sangue , Plaquetas/metabolismo , Isquemia Encefálica/sangue , Proteína C-Reativa/análise , Linfócitos T CD4-Positivos/metabolismo , Ligante de CD40/sangue , Contagem de Células , Quimiocina CCL2/sangue , Feminino , Citometria de Fluxo , Seguimentos , Humanos , Ataque Isquêmico Transitório/sangue , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Selectina-P/metabolismo , Adesividade Plaquetária , Receptores de Interleucina-2/biossíntese , Valores de Referência , Regulação para Cima
8.
Arch Neurol ; 58(5): 771-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11346372

RESUMO

BACKGROUND: Ictal fear (IF) is most frequently associated with epileptic discharges from mesial temporal areas. OBJECTIVES: To determine whether patients with IF were more likely to become seizure free after anteromesial temporal lobe resection compared with those without IF and whether they show more anteriorly pronounced metabolic changes assessed by means of multivoxel magnetic resonance spectroscopy (MRS) along the hippocampal axis. METHODS: Surgical outcome was assessed in 33 consecutive patients with temporal lobe epilepsy after a mean follow-up of 25 months (range, 12-38 months). Proton multivoxel MRS of the hippocampal formation was applied to detect regional differences along the axis of the hippocampus in patients with and without IF. Magnetic resonance tomography showed typical features of hippocampal sclerosis in all patients. RESULTS: Twelve (36%) of the 33 patients reported fear at the beginning of their habitual seizures. Eleven of these patients were seizure free postoperatively. In contrast, only 11 of 21 patients without IF had a favorable outcome. Results of MRS revealed significantly higher pathologic N-acetylaspartate-choline ratios in the anterior portion of the hippocampal formation in patients with than in those without IF, indicating focal metabolic and/or morphologic changes in the head of the hippocampus. CONCLUSIONS: These results indicate the importance of diagnosing auras with IF to provide a more detailed prognosis of the surgical outcome. In addition, our data emphasize that multivoxel MRS is a valuable tool in the presurgical evaluation, as it may reveal different topographical patterns of hippocampal sclerosis.


Assuntos
Ácido Aspártico/análogos & derivados , Epilepsia do Lobo Temporal/psicologia , Epilepsia do Lobo Temporal/cirurgia , Medo , Adulto , Ácido Aspártico/metabolismo , Colina/metabolismo , Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/metabolismo , Feminino , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose , Resultado do Tratamento
9.
J Neurol Sci ; 215(1-2): 21-5, 2003 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-14568123

RESUMO

Proton MR spectroscopy offers an additional noninvasive method of supporting focus lateralization in patients with intractable temporal lobe epilepsy. In this study involving 57 patients, the ability of multivoxel 1H-MRS to differentiate between mesial and lateral TLE was investigated in addition to its ability to lateralize the epileptogenic focus. Temporal lobe epilepsy (TLE) was classified into mesiobasal or lateral temporal lobe epilepsy according to the results of preoperative diagnostics including neurological and neuropsychological examinations, video-EEG monitoring and high resolution MRI. 1H-MR-spectroscopy (1H-MRS) showed that pathological changes in the mesial temporal lobes indicate a predominance in different parts of the ipsilateral temporal lobe (hippocampal and parahippocampal areas) correlating to the clinically defined groups. In addition, mesiobasal TLE tends to have higher concomitant contralateral abnormalities. Our results reveal that 1H-MRS is able to distinguish between mesiobasal and lateral pathologies in patients with TLE and represents a useful tool for noninvasive TLE classification.


Assuntos
Epilepsia do Lobo Temporal/classificação , Epilepsia do Lobo Temporal/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Prótons , Adulto , Eletroencefalografia/métodos , Epilepsia do Lobo Temporal/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Eur J Radiol ; 33(3): 170-7, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10699734

RESUMO

PURPOSE: This paper intends to demonstrate the possibilities of two- and three-dimensional visualisation methods from spiral-CT data sets in the head and neck region and demonstrates their value based on various studies. MATERIAL AND METHODS: The scanner was a Somatom PLUS 4 (Siemens, Forchheim/Germany). The patients were scanned using a slice thickness of 3 mm and a table feed of 5 mm (pitch 1,6). The images were reconstructed with an increment of 1 mm. Contrast agent (150 ml) was applied intravenously with a flow of 2.5 ml/s and a start delay of 80 s. In one study the start delay was 20 s in order to visualise the carotid arteries (extracranial aneurysm). Volumetric data sets were postprocessed with 'Vitrea' and 'VoxelView' (Vital Images) volume rendering software on a Silicon Graphics O2 workstation (virtual laryngoscopy). Multiplanar reformation and colour-coded 3D-reconstruction were done on a Prominence workstation (Siemens/Forchheim/Germany). RESULTS: In every region of the head and neck MPRs are useful as additional planes (with the exception of the hypopharynx and the larynx), SSDs are always useful if there is extensive bony destruction (skull, spine, skeleton larynx). Colour-coded three-dimensional reformations may be done for extensive tumours and before multi-specialty surgery. Perspective volume rendering is already in use for virtual endoscopy of the paranasal sinuses and the virtual laryngoscopy. In temporal bone evaluation, perspective volume rendering is a new and promising method of the future to assess the inner ear. SUMMARY: Two- and three-dimensional displays are used to visualise pathological findings in their topographic relation to anatomical leading structures. Thus, the radiologist can point out to the clinician the pathological findings by some essential images without having to demonstrate all axial slices.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Aneurisma/diagnóstico por imagem , Angiofibroma/diagnóstico por imagem , Artéria Carótida Externa/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/irrigação sanguínea , Humanos , Neoplasias Laríngeas/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias dos Seios Paranasais/diagnóstico por imagem , Neoplasias Faríngeas/diagnóstico por imagem , Osso Temporal/diagnóstico por imagem , Articulação Temporomandibular/diagnóstico por imagem , Tomografia Computadorizada por Raios X/instrumentação
11.
Clin Neurol Neurosurg ; 103(3): 191-3, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11532562

RESUMO

Recently, prothrombin gene mutation G20210A has been associated with elevated thrombosis risk and rarely with cerebral vein thrombosis (CVT). Three patients are described who had this genetic predisposition and who developed CVT in an unusual constellation with other factors. In the first patient, the intake of valproic acid (VPA) may have played an aggravating role in the development of CVT; in the second patient diagnosis of coagulation disorder was made during pregnancy consultation 6 years after CVT; in the third patient the CVT occurred at the age of 78 years. In patients with CVT, coagulation-examinations should include tests for the prothrombin gene (G20210A) mutation.


Assuntos
Veias Cerebrais , Trombose Intracraniana/genética , Mutação/genética , Protrombina/genética , Trombose Venosa/genética , Adulto , Fatores Etários , Idoso , Transtornos da Coagulação Sanguínea/complicações , Feminino , Predisposição Genética para Doença/etiologia , Predisposição Genética para Doença/genética , Humanos , Trombose Intracraniana/etiologia , Ácido Valproico/efeitos adversos , Trombose Venosa/etiologia
12.
Nuklearmedizin ; 42(5): 215-9, 2003 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-14571318

RESUMO

AIM: Although the fusion of images from different modalities may improve diagnostic accuracy, it is rarely used in clinical routine work due to logistic problems. Therefore we evaluated performance and time needed for fusing MRI and SPECT images using a semiautomated dedicated software. PATIENTS, MATERIAL AND METHOD: In 32 patients regional cerebral blood flow was measured using (99m)Tc ethylcystein dimer (ECD) and the three-headed SPECT camera MultiSPECT 3. MRI scans of the brain were performed using either a 0,2 T Open or a 1,5 T Sonata. Twelve of the MRI data sets were acquired using a 3D-T1w MPRAGE sequence, 20 with a 2D acquisition technique and different echo sequences. Image fusion was performed on a Syngo workstation using an entropy minimizing algorithm by an experienced user of the software. The fusion results were classified. We measured the time needed for the automated fusion procedure and in case of need that for manual realignment after automated, but insufficient fusion. RESULTS: The mean time of the automated fusion procedure was 123 s. It was for the 2D significantly shorter than for the 3D MRI datasets. For four of the 2D data sets and two of the 3D data sets an optimal fit was reached using the automated approach. The remaining 26 data sets required manual correction. The sum of the time required for automated fusion and that needed for manual correction averaged 320 s (50-886 s). CONCLUSION: The fusion of 3D MRI data sets lasted significantly longer than that of the 2D MRI data. The automated fusion tool delivered in 20% an optimal fit, in 80% manual correction was necessary. Nevertheless, each of the 32 SPECT data sets could be merged in less than 15 min with the corresponding MRI data, which seems acceptable for clinical routine use.


Assuntos
Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Cisteína/análogos & derivados , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Automação/métodos , Encéfalo/anatomia & histologia , Encéfalo/irrigação sanguínea , Cisteína/farmacocinética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Compostos de Organotecnécio/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único/normas
15.
AJNR Am J Neuroradiol ; 32(9): 1632-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21816919

RESUMO

BACKGROUND AND PURPOSE: CT perfusion data sets are commonly acquired using a temporal resolution of 1 image per second. To limit radiation dose and allow for increased spatial coverage, the reduction of temporal resolution is a possible strategy. The aim of this study was to evaluate the effect of reduced temporal resolution in CT perfusion scans with regard to color map quality, quantitative perfusion parameters, ischemic lesion extent, and clinical decision-making when using DC and MS algorithms. MATERIALS AND METHODS: CTP datasets from 50 patients with acute stroke were acquired with a TR of 1 second. Two-second TR datasets were created by removing every second image. Various perfusion parameters (CBF, CBV, MTT, TTP, TTD) and color maps were calculated by using identical data-processing settings for 2-second and 1-second TR. Color map quality, quantitative region-of-interest-based perfusion measurements, and TAR/NVT lesions (indicated by CBF/CBV mismatch) derived from the 2-second and 1-second processed data were statistically compared. RESULTS: Color map quality was similar for 2-second versus 1-second TR when using DC and was reduced when using MS. Regarding quantitative values, differences between 2-second and 1-second TR datasets were statistically significant by using both algorithms. Using DC, corresponding tissue-at-risk lesions were slightly smaller at 2-second versus 1-second TR (P < .05), whereas corresponding NVT lesions showed excellent agreement. With MS, corresponding tissue-at-risk lesions showed excellent agreement but more artifacts, whereas NVT lesions were larger (P < .001) compared with 1-second TR. Therapeutic decisions would have remained the same in all patients. CONCLUSIONS: CTP studies obtained with 2-second TR are typically still diagnostic, and the same therapy would have been provided. However, with regard to perfusion quantitation and image-quality-based confidence, our study indicates that 1-second TR is preferable to 2-second TR.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Imagem de Perfusão/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Idoso , Algoritmos , Bases de Dados Factuais/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Estudos Retrospectivos
16.
AJNR Am J Neuroradiol ; 31(9): 1690-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20581066

RESUMO

BACKGROUND AND PURPOSE: PCT postprocessing commonly uses either the MS or a variant of the DC approach for modeling of voxel-based time-attenuation curves. There is an ongoing discussion about the respective merits and limitations of both methods, frequently on the basis of theoretic reasoning or simulated data. We performed a qualitative and quantitative comparison of DC and MS by using identical source datasets and preprocessing parameters. MATERIALS AND METHODS: From the PCT data of 50 patients with acute ischemic stroke, color maps of CBF, CBV, and various temporal parameters were calculated with software implementing both DC and MS algorithms. Color maps were qualitatively categorized. Quantitative region-of-interest-based measurements were made in nonischemic GM and WM, suspected penumbra, and suspected infarction core. Qualitative results, quantitative results, and PCT lesion sizes from DC and MS were statistically compared. RESULTS: CBF and CBV color maps based on DC and MS were of comparably high quality. Quantitative CBF and CBV values calculated by DC and MS were within the same range in nonischemic regions. In suspected penumbra regions, average CBF(DC) was lower than CBF(MS). In suspected infarction core regions, average CBV(DC) was similar to CBV(MS). Using adapted tissue-at-risk/nonviable-tissue thresholds, we found excellent correlation of DC and MS lesion sizes. CONCLUSIONS: DC and MS yielded comparable qualitative and quantitative results. Lesion sizes indicated by DC and MS showed excellent agreement when using adapted thresholds. In all cases, the same therapy decision would have been made.


Assuntos
Algoritmos , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Imagem de Perfusão/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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