Biomedical subjects

Ernst Klotz

Publications and source records attributed to Ernst Klotz.

17 recordsLinked to original sources

PubMed2006

Quantitative prediction of contrast enhancement from test bolus data in cardiac MSCT.

The purpose of this study was to evaluate a new algorithm for the prediction of contrast enhancement from test bolus data in cardiac multislice spiral computed tomography (MSCT). An algorithm for the prediction of contrast enhancement using test bolus data was developed. A total of 30 consecutive patients (15 male, 69.5 +/- 9.6 years) underwent cardiac MSCT (12 x 0.75 mm, 120 kV, 500 mAs(eff.)) with a biphasic contrast material injection protocol. Contrast timing was derived from a standard 20 ml test bolus injection. Based on the test bolus time attenuation curves, expected enhancement values were computed for the ascending and descending aorta and the pulmonary trunk and compared with measured data from the cardiac CT scan. At the level of the test bolus measurement in the ascending aorta, the corresponding attenuation values were 309.4 +/- 49.6 Hounsfield Units (HU) for the predicted and 285.6 +/- 42.6 HU for the measured attenuation, respectively. The mean deviation between predicted and measured CT values was 32.8 +/- 48.2 HU (upper and lower limits of agreement 101.4/-53.8 HU), indicating a slight systematic tendency for overestimation. For 80% of the patients the prediction error was less than 50 HU. Prediction of contrast enhancement in cardiac MSCT from test bolus data is feasible with a relatively small mean deviation; 80% of the predictions were within a range that might be acceptable for routine clinical application.

Aged↗

PubMed2006

The accuracy of 1- and 3-mm slices in coronary calcium scoring using multi-slice CT in vitro and in vivo.

The accuracy of coronary calcium scoring using 16-row MSCT comparing 1- and 3-mm slices was assessed. A thorax phantom with calcium cylinder inserts was scanned applying a non-enhanced retrospectively ECG-gated examination protocol: collimation 12 x 0.75 mm; 120 kV; 133 mAs(eff). Thirty-eight patients were examined using the same scan protocol. Image reconstruction was performed with an effective slice thickness of 3 and 1 mm. The volume score, calcium mass and Agatston score were determined. Image noise was measured in both studies. The volume score and calcium mass varied less than the Agatston score. The overall measured calcium mass compared to the actual calcium mass revealed a relative difference of +2.0% for 1-mm slices and -1.2% for 3-mm slices. Due to increased image noise in thinner slices in the patient study (26.1 HU), overall calcium scoring with a scoring threshold of 130 HU was not feasible. Interlesion comparison showed significantly higher scoring results for thinner slices (all P<0.001). A similar accuracy comparing calcium scoring results of 1- and 3-mm slices was shown in the phantom study; therefore, the potentially necessary increase of the patient's dose in order to achieve assessable 1-mm slices with an acceptable image-to-noise-ratio appears not to be justified.

Aged↗

PubMed2006

Lung cancer perfusion at multi-detector row CT: reproducibility of whole tumor quantitative measurements.

Institutional review board approval and informed consent were obtained for this study. The aim of the study was to prospectively assess, in patients with lung cancer, the reproducibility of a quantitative whole tumor perfusion computed tomographic (CT) technique. Paired CT studies were performed in 10 patients (eight men, two women; mean age, 66 years) with lung cancer. Whole tumor permeability and blood volume were measured, and reproducibility was evaluated by using Bland-Altman statistics. Coefficient of variation of 9.49% for permeability and 26.31% for blood volume and inter- and intraobserver variability ranging between 3.30% and 6.34% indicate reliable assessment with this whole tumor technique.

Aged↗

PubMed2006

New techniques in CT angiography.

Computed tomographic (CT) angiography has been improved significantly with the introduction of four- to 64-section spiral CT scanners, which offer rapid acquisition of isotropic data sets. A variety of techniques have been proposed for postprocessing of the resulting images. The most widely used techniques are multiplanar reformation (MPR), thin-slab maximum intensity projection, and volume rendering. Sophisticated segmentation algorithms, vessel analysis tools based on a centerline approach, and automatic lumen boundary definition are emerging techniques; bone removal with thresholding or subtraction algorithms has been introduced. These techniques increasingly provide a quality of vessel analysis comparable to that achieved with intraarterial three-dimensional rotational angiography. Neurovascular applications for these various image postprocessing methods include steno-occlusive disease, dural sinus thrombosis, vascular malformations, and cerebral aneurysms. However, one should keep in mind the potential pitfalls of these techniques and always double-check the final results with source or MPR imaging.

Algorithms↗

PubMed2006

Quantitative assessment of lung cancer perfusion using MDCT: does measurement reproducibility improve with greater tumor volume coverage?

OBJECTIVE: To date, quantitative assessment of tumor vascularity using perfusion CT has been limited to a single tumor level, with the potential for measurement error in heterogeneous tumors. We aimed to determine if greater z-axis tumor coverage improves the reproducibility of perfusion CT measurements in lung cancer. SUBJECTS AND METHODS: Paired perfusion studies were performed on 10 patients who had histologically confirmed advanced non-small cell lung cancer. Using 16-MDCT, multiple sequential volumetric acquisitions encompassing the entire tumor were acquired after infusion of i.v. contrast material. Using Patlak analysis, median values of tumor permeability (mL/100 mL/min) and blood volume (mL/100 mL) were measured for 10-mm z-axis coverage, and for 40-mm z-axis coverage in each of the paired perfusion studies. Measurement reproducibility was evaluated using Bland-Altman statistics. RESULTS: Mean difference (95% limits of agreement) for tumor permeability was 1.4 (-4.0 to 6.8) for 10-mm coverage and 0.8 (-3.6 to 5.2) for 40-mm coverage. Mean difference (95% limits of agreement) for blood volume was 1.9 (-5.1 to 8.9) for 10-mm coverage and 1.4 (-3.7 to 6.6) for 40-mm coverage. The coefficient of variation for permeability was 18.7% for 10-mm coverage, improving to 11.9% for 40-mm coverage. The coefficient of variation for blood volume was 41.7% for 10-mm coverage, improving to 32.6% for 40-mm coverage. CONCLUSION: Our results show that an improvement in tumor perfusion measurement reproducibility may be achieved with greater z-axis coverage.

Aged↗

PubMed2005

Multislice computed tomography perfusion imaging for visualization of acute pulmonary embolism: animal experience.

The purpose of our animal study was to evaluate a new computed tomography (CT) subtraction technique for visualization of perfusion defects within the lung parenchyma in subsegmental pulmonary embolism (PE). Seven healthy pigs were entered into a prospective trial. Acute PE was artificially induced by fresh clot material prior to the CT scans. Within a single breath-hold, whole thorax CT scans were performed with a 16-slice multidetector-row CT scanner (SOMATOM Sensation 16; Siemens, Forchheim, Germany) before and after intravenous application of 80 ml of contrast medium with a flow rate of 4 ml/s, followed by a saline chaser. The scan parameters were 120 kV and 100 mAs(eff), using a thin collimation of 16x0.75 mm and a table speed/rotation of 15-18 mm (pitch, 1.25-1.5; rotation time, 0.5 s). Axial source images were reconstructed with an effective slice thickness of 1 mm (overlap, 30%). A new automatic subtraction technique was used. After 3D segmentation of the lungs in the plain and contrast-enhanced series, threshold-based extraction of major airways and vascular structures in the contrast images was performed. This segmentation was repeated in the plain CT images segmenting the same number of vessels and airways as in the contrast images. Both scans were registered onto each other using nonrigid registration. After registration both image sets were filtered in a nonlinear fashion excluding segmented airways and vessels. After subtracting the plain CT data from the contrast data the resulting enhancement images were color-encoded and overlaid onto the contrast-enhanced CT angiography (CTA) images. This color-encoded combined display of parenchymal enhancement of the lungs was evaluated interactively on a workstation (Leonardo, Siemens) in axial, coronal and sagittal plane orientations. Axial contrast-enhanced CTA images were rated first, followed by an analysis of the combination images. Finally, CTA images were reread focusing on areas with perfusion deficits indicating PE on the color-coded enhancement display. Subtraction was feasible for all seven studies. In one animal, opacification of the pulmonary arteries was suboptimal owing to heart insufficiency. In the remaining six pigs, a total of 37 perfusion defects were clearly assessable downstream of occluded subsegmental arteries, showing lower or missing enhancement compared with normally perfused lung parenchyma. Indeterminate findings from CTA showed typical PE perfusion defects in four out of six cases on CT subtraction. Additionally, 22 peripheral triangular-shaped enhancement defects were delineated. Nine of these findings were reclassified as definitely being caused by PE on second reading of the CTA data sets. Our initial results have shown that this new subtraction technique for perfusion imaging of PE is feasible, using routine contrast delivery. Dedicated examination protocols are mandatory for adequate opacification of the pulmonary arteries and for optimization of data sets for subsequent subtraction. Perfusion imaging allows a comprehensive assessment of morphology and function, providing more accurate information on acute PE.

Angiography↗

PubMed2005

Approaches to CT perfusion imaging in pulmonary embolism.

Computed tomography (CT) has become an increasingly accepted technique and is the method of choice for direct visualization of pulmonary emboli (PE). The quantitative assessment of tissue perfusion may yield more important information for patient management than the direct visualization of emboli by CT alone. Several attempts have been made to measure pulmonary blood flow by administration of intravenous contrast material. In this article, various experimental CT approaches for visualization and quantification of pulmonary perfusion are discussed. Ideally, CT will be able to provide both structural and functional information. Simple measurement of lung density before and after intravenous contrast delivery has been performed with single-slice CT technology using region-of-interest methodology. For electron-beam CT, a repeated data acquisition on a 7.6-cm lung volume has proven to be technically feasible. Using such dynamic scanning, reduced blood flow was observed in occluded lung segments. Color-encoded parenchymal density distribution in the axial, coronal, and sagittal planes was derived from thin collimation data sets using four-row multi-slice spiral CT (MSCT). Initial animal data from 16-slice MSCT offer a real CT-subtraction technique of the entire chest for the first time.

Color↗

PubMed2005

Radiation dose reduction to the male gonads during MDCT: the effectiveness of a lead shield.

OBJECTIVE: Our study was designed to quantify the effect of a standard gonad shield on the testicular radiation exposure due to scatter during routine abdominopelvic MDCT. SUBJECTS AND METHODS: Routine abdominopelvic MDCT was performed in 34 patients with gonadal lead shielding and 32 patients without this shielding; the testes were not exposed to the direct beam during the examination. We estimated the testicular dose administered with thermoluminescent dosimetry, taking into account each patient's body weight and body mass index (BMI). RESULTS: With a 1-mm lead shield, the mean testicular dose was reduced from 2.40 to 0.32 mSv, a reduction of 87%. The difference was found to be statistically significant (p < 0.0001). No correlation between testicular dose and body weight or BMI was found. CONCLUSION: Shielding the male gonads reduces the testicular radiation dose during abdominopelvic MDCT significantly and can be recommended for routine use.

Adult↗

PubMed2004

Acute stroke assessment with CT: do we need multimodal evaluation?

PURPOSE: To assess detection of stroke and prediction of extent of infarction with multimodal computed tomographic (CT) evaluation (unenhanced CT, perfusion CT, and CT angiography) in patients suspected of having acute stroke. MATERIALS AND METHODS: Forty-four consecutive patients with a mean National Institutes of Health Stroke Scale score of 10.45 and suspected of having ischemic stroke of the anterior circulation were examined with multi-detector row CT within 8 hours (mean, 3.05 hours) of onset of symptoms. All evaluations were performed with the knowledge that acute stroke was suspected but without detailed clinical information. The extent of ischemia or final infarction on the baseline unenhanced CT scan and follow-up images was assessed with the Alberta Stroke Program Early CT score. Different perfusion maps and follow-up images were assessed to determine the percentage of the ischemia-affected hemisphere. Each component, as well as the multimodal CT evaluation, was compared with follow-up unenhanced CT scans or magnetic resonance images after a mean time of 2.32 days. RESULTS: Multimodal CT revealed true-positive findings in 30 of 41 patients and true-negative findings in three, resulting in a sensitivity of 78.9%. Unenhanced CT, CT angiography, and perfusion CT showed sensitivities of 55.3%, 57.9%, and 76.3%, respectively. In eight patients, small infarctions (mean size, 1.47 cm) that were proved at follow-up were missed with all modalities at initial multimodal CT. With perfusion CT, four of these small infarctions were missed within the white matter of the section levels. Maps of cerebral blood flow showed the best correlation with the final size of infarction with an r(2) value of 0.71. CONCLUSION: The presented multimodal CT evaluation improves detection rate and prediction of the final size of infarction in comparison with unenhanced CT, CT angiography, and perfusion CT alone.

Adult↗

PubMed2004

Comparison of perfusion computed tomography and computed tomography angiography source images with perfusion-weighted imaging and diffusion-weighted imaging in patients with acute stroke of less than 6 hours' duration.

BACKGROUND AND PURPOSE: We aimed to determine the diagnostic value of perfusion computed tomography (PCT) and CT angiography (CTA) including CTA source images (CTA-SI) in comparison with perfusion-weighted magnetic resonance imaging (MRI) (PWI) and diffusion-weighted MRI (DWI) in acute stroke <6 hours. METHODS: Noncontrast-enhanced CT, PCT, CTA, stroke MRI, including PWI and DWI, and MR angiography (MRA), were performed in patients with symptoms of acute stroke lasting <6 hours. We analyzed ischemic lesion volumes on patients' arrival as shown on NECT, PCT, CTA-SI, DWI, and PWI (Wilcoxon, Spearman, Bland-Altman) and compared them to the infarct extent as shown on day 5 NECT. RESULTS: Twenty-two stroke patients underwent CT and MRI scanning within 6 hours. PCT time to peak (PCT-TTP) volumes did not differ from PWI-TTP (P=0.686 for patients who did not undergo thrombolysis/P=0.328 for patients who underwent thrombolysis), nor did PCT cerebral blood volume (PCT-CBV) differ from PWI-CBV (P=0.893/P=0.169). CTA-SI volumes did not differ from DWI volumes (P=0.465/P=0.086). Lesion volumes measured in PCT maps significantly correlated with lesion volumes on PWI (P=0.0047, r=1.0/P=0.0019, r=0.897 for TTP; P=0.0054, r=0.983/P=0.0026, r=0.871 for CBV). Also, PCT-CBV lesion volumes significantly correlated with follow-up CT lesion volumes (P=0.0047, r=1.0/P=0.0046, r=0.819). CONCLUSIONS: In hyperacute stroke, the combination of PCT and CTA can render important diagnostic information regarding the infarct extent and the perfusion deficit. Lesions on PCT-TTP and PCT-CBV do not differ from lesions on PWI-TTP and PWI-CBV; lesions on CTA source images do not differ from lesions on DWI. The combination of noncontrast-enhanced CT (NECT), perfusion CT (PCT), and CT angiography (CTA) can render additional information within <15 minutes and may help in therapeutic decision-making if PWI and DWI are not available or cannot be performed on specific patients.

Adult↗

PubMed2004

Determination of cardiac output with multislice spiral computed tomography: a validation study.

OBJECTIVE: To validate and to determine the reproducibility of cardiac output (CO) measurements based on a test-bolus examination in multislice spiral computed tomography (MSCT) in comparison with invasively measured CO using the thermal dilution technique. MATERIAL AND METHODS: In 8 swine, CO was determined by invasive thermal dilution technique and by analysis of enhancement data from dynamic MSCT test-bolus examinations. To assess reproducibility, all MSCT examinations were performed twice. Results were compared using Pearson's correlation coefficient and Bland-Altman plots. RESULTS: Measure by thermal dilution technique CO was 3.71 +/- 1.12 L/min, whereas CO was 3.67 +/- 1.30 L/min using MSCT. Pearson's correlation coefficient was 0.89. The average deviation between MSCT and thermal dilution technique was 0.04 L/min with a standard deviation of 0.59 L/min. There was a good agreement between both MSCT measurements with a mean deviation of -0.03 L/min and a standard deviation of 0.51 L/min. CONCLUSION: CO can reliably be determined from MSCT by means of indicator dilution technique. Measurements are reproducible and provide valuable information on the overall cardiovascular performance without application of additional contrast material or radiation. As this technique does not require time-consuming postprocessing it can be added to routine reporting.

Animals↗

PubMed2003

Volumetric measurements of pulmonary nodules at multi-row detector CT: in vivo reproducibility.

The aim of this study was to assess the in vivo measurement precision of a software tool for volumetric analysis of pulmonary nodules from two consecutive low-dose multi-row detector CT scans. A total of 151 pulmonary nodules (diameter 2.2-20.5 mm, mean diameter 7.4+/-4.5 mm) in ten subjects with pulmonary metastases were examined with low-dose four-detector-row CT (120 kVp, 20 mAs (effective), collimation 4x1 mm, normalized pitch 1.75, slice thickness 1.25 mm, reconstruction increment 0.8 mm; Somatom VolumeZoom, Siemens). Two consecutive low-dose scans covering the whole lung were performed within 10 min. Nodule volume was determined for all pulmonary nodules visually detected in both scans using the volumetry tool included in the Siemens LungCare software. The 95% limits of agreement between nodule volume measurements on different scans were calculated using the Bland and Altman method for assessing measurement agreement. Intra- and interobserver agreement of volume measurement were determined using repetitive measurements of 50 randomly selected nodules at the same scan by the same and different observers. Taking into account all 151 nodules, 95% limits of agreement were -20.4 to 21.9% (standard error 1.5%); they were -19.3 to 20.4% (standard error 1.7%) for 105 nodules <10 mm. Limits of agreement were -3.9 to 5.7% for intraobserver and -5.5 to 6.6% for interobserver agreement. Precision of in vivo volumetric analysis of nodules with an automatic volumetry software tool was sufficiently high to allow for detection of clinically relevant growth in small pulmonary nodules.

Adult↗

PubMed2003

Multidetector-row computed tomography of the coronary arteries: predictive value and quantitative assessment of non-calcified vessel-wall changes.

The aim of this study was to quantitatively assess non-calcified coronary artery plaques and to determine their predictive value for the detection of coronary artery disease (CAD). A total of 179 patients underwent a calcium screening examination and a contrast-enhanced multidetector-row computed tomography angiography (MDCT) of the coronary arteries for various indications. The traditional calcium scores were evaluated and all examinations were reviewed for the presence of non-calcified plaques with an attenuation of 0-130 Hounsfield units (HU). The number, mean attenuation, and volume of these non-calcified plaques were recorded. All patients also underwent conventional catheter angiography. Coronary calcium was detected in 73% (131 of 179) of the patients. Overall incidence of purely non-calcified plaques was 30% (53 of 179). In 27% of the patients (48 of 179) no calcium was detected; however, 15% of these patients without calcifications showed non-calcified plaques (7 of 48). Significant correlations were found between the volume of calcified plaques, volume of non-calcified plaques, and total plaque volume. There were significant differences in plaque composition comparing different risk factor profiles and different stages of CAD. Volumetric assessment of non-calcified coronary artery plaques is feasible using contrast-enhanced MDCT. Screening for non-calcified plaques identifies patients with signs of CAD that are missed in a calcium screening examination.

Calcinosis↗

PubMed2003

Measurement of cardiac output from a test-bolus injection in multislice computed tomography.

The aim of this study was to assess the feasibility of non-invasive determination of cardiac function from test-bolus data in multislice spiral computed tomography (MSCT). In 25 patients enhancement data gathered from a standardized test-bolus injection were analyzed. The test-bolus examination was performed prior to a retrospectively ECG-gated MSCT of the heart. A time-attenuation curve was obtained in the ascending aorta at the level of the pulmonary arteries. A gamma variate fit was applied to the curve in order to exclude recirculation and get pure first-pass data. Using the known amount of iodine injected, cardiac output (CO), and stroke volume (SV) were determined from integration of the fitted contrast enhancement curve using a reformation of the Stewart-Hamilton equation. Results were compared with CO and SV calculated from the geometric analysis of the retrospectively gated MSCT data using the ARGUS Software (Siemens, Forchheim, Germany). The CO and SV determined from test-bolus analysis and from geometric analysis correlated well with Pearson's correlation coefficients of 0.87 and 0.88, respectively. The standard deviation of the difference between both methods was 0.51 l/min for CO (8.6%) and 11.0 ml for SV (12.3%). Non-invasive quantification of CO seems to be feasible from a standard test-bolus injection. It provides valuable information on cardiac function without additional radiation or application of contrast material.

Cardiac Output↗

PubMed2002

Correlation of apparent diffusion coefficient and computed tomography density in acute ischemic stroke.

BACKGROUND AND PURPOSE: Diffusion-weighted MR imaging is very sensitive for the detection of restricted molecular water diffusion in acute ischemic stroke. CT is sensitive to net water uptake in ischemic edema. We compared the decrease in the apparent diffusion coefficient (ADC) in diffusion-weighted MR imaging with CT density changes to study the correlation between diffusion restriction and water uptake in acute stroke patients. METHODS: Twenty-five patients with acute ischemic stroke of the anterior cerebral circulation underwent MR and CT imaging 1.3 to 5.4 hours after symptom onset. ADC and CT data were transferred into a common 3-dimensional space, and regions of decreased ADC (dADC) were superimposed onto the corresponding CT. Mean values of ADC and Hounsfield units (HU) were determined in comparison with the nonaffected hemisphere. RESULTS: Mean decrease in ADC (dADC) was 170+/-53x 10(-6) mm2/s and corresponded to a decrease (dCT) in CT density of 1.3+/-0.7 HU. dCT showed a continuous linear decrease of 0.4 HU/h (r=0.55, P<0.01), whereas the decrease is ADC was almost complete after 1.5 hours. A correlation between the decrease in ADC and dCT was found (r=0.41, P=0.04). CONCLUSIONS: The severity of diffusion restriction correlates with net water uptake in acute ischemic stroke. However, the underlying pathophysiology and different time courses indicate a common reason rather than a direct causality for both phenomena. The time delay and low value of CT density changes provide a reasonable explanation for the higher sensitivity of MR imaging in ischemic stroke.

Acute Disease↗

PubMed2002

MOSAIC: Multimodal Stroke Assessment Using Computed Tomography: novel diagnostic approach for the prediction of infarction size and clinical outcome.

BACKGROUND AND PURPOSE: With new CT technologies, including CT angiography (CTA), perfusion CT (PCT), and multidetector row technique, this method has regained interest for use in acute stroke assessment. We have developed a score system based on Multimodal Stroke Assessment Using CT (MOSAIC), which was evaluated in this prospective study. METHODS: Forty-four acute stroke patients (mean age, 63.8 years) were enrolled within a mean of 3.0+/-1.9 hours after symptom onset. The MOSAIC score (0 to 8 points) was generated by results of the 3 sequential CT investigations: (1) presence and amount of early signs of infarction on noncontrast CT (NCCT; 0 to 2 points), (2) stenosis (>50%) or occlusion of the distal internal carotid or middle cerebral artery on CTA (0 to 2 points), and (3) presence and amount of reduced cerebral blood flow on 2 adjacent PCT slices (0 to 4 points). The predictive value of the MOSAIC score was compared with each single CT component with respect to the final size of infarction and the clinical outcome 3 months after stroke by use of the modified Rankin Scale (mRS) and the Barthel Index (BI). RESULTS: Among the CT components, PCT showed the best correlation to infarction size (r=0.75) and clinical outcome (r=0.60 to 0.62) compared with NCCT (r=0.43 to 0.58) and CTA (r=0.47 to 0.71). The MOSAIC score showed consistently higher correlation factors (r=0.67 to 0.78) and higher predictive values (0.73 to 1.0) than all single CT components with respect to outcome measures. A MOSAIC score <4 predicted independence with 89% to 96% likelihood (mRS </=2, BI >/=90); a MOSAIC score <5 predicted fair outcome with 96% to 100% likelihood (mRS </=3, BI >/=60). CONCLUSIONS: The MOSAIC score based on multidetector row CT technology is superior to NCCT, CTA, and PCT in predicting infarction size and clinical outcome in hyperacute stroke.

Acute Disease↗

PubMedDate not supplied

Comprehensive imaging of ischemic stroke with multisection CT.

Computed tomography (CT) is an established tool for the diagnosis of ischemic or hemorrhagic stroke. Nonenhanced CT can help exclude hemorrhage and detect "early signs" of infarction but cannot reliably demonstrate irreversibly damaged brain tissue in the hyperacute stage of ischemic stroke. Further evaluation of patients with ischemic stroke should include differentiation between reversible and irreversible brain damage, which is essential for choosing an appropriate therapy. Perfusion CT provides information about brain perfusion, which permits differentiation of irreversibly damaged brain tissue from reversibly impaired "tissue at risk." CT angiography can help detect stenosis or occlusion of extra- and intracranial arteries. Multisection CT allows the combined use of all three imaging modalities-nonenhanced CT, perfusion CT, and CT angiography-to rapidly obtain comprehensive information regarding the extent of ischemic damage in acute stroke patients. Specific patterns of findings are typically seen in ischemic stroke and can be analyzed more accurately with the combined use of multisection CT and MR imaging. Nevertheless, prospective studies involving a large number of patients will be needed to ascertain the treatment of choice for patients with each of these patterns of findings.

Brain Ischemia↗