Whole brain CT perfusion deficits using 320-detector-row CT scanner in TIA patients are associated with ABCD2 score
Bijal MehtaGhulam MustafaAaron McMurtrayMohammed W. MasudSameer GunukulaHaris KamalAmit KandelAbdelrahman BeltagyPing Li
6
Citation
20
Reference
10
Related Paper
Citation Trend
Abstract:
Background: Transient ischemic attacks (TIA) are cerebral ischemic events without infarction. The uses of CT perfusion (CTP) techniques such as cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT) and cerebral blood flow (CBF) provide real time data about ischemia. It has been shown that CTP changes occur in less sensitive CTP scanners in patients with TIA. Larger detector row CTP (whole brain perfusion studies) may show that CTP abnormalities are more prevalent than previously noted. It is also unclear if these changes are associated with TIA severity. Objective: To demonstrate that TIA patients are associated with perfusion deficits using whole brain 320-detector-row CT perfusion, and to determine an association between ABCD2 score and perfusion deficit using whole brain perfusion. Methods: We retrospectively reviewed all TIA patients for CTP deficits from 2008–2010. Perfusion imaging was reviewed at admission; and it was determined if a perfusion deficit was present along with vascular territory involved. Results: Of 364 TIA patients, 62 patients had CTP deficits. The largest group of patients had MCA territory involved with 48 of 62 patients (77.42%). The most common perfusion abnormality was increased TTP with 46 patients (74.19%). The ABCD2 score was reviewed in association with perfusion deficit. Increased age >60, severe hypertension (>180/100 mmHg), patients with speech abnormalities, and duration of symptoms >10 min were associated with a perfusion deficit but history of diabetes or minimal/moderate hypertension (140/90–179/99 mmHg) was not. There was no association between motor deficit and perfusion abnormality. Conclusion: Perfusion deficits are found in TIA patients using whole brain CTP and associated with components of the ABCD2 score.Keywords:
Stroke
Abnormality
Objective:To introduce a method of making MR cerebral perfusion weighted imaging based on Personal Computer (PC) and probe into the clinical diagnostic value of the method.Methods:MR cerebral perfusion weighted imaging was performed in 5 normal adults and 18 patients with cerebral ischemia.Perfusion-weighted images were analyzed with a software running on PC.Cerebral perfusion mapping with parameters including relative regional cerebral blood flow (rrCBF),relative regional cerebral blood volume (rrCBV),time to peak (TTP) and bolus mean transit time (bMTT) were conducted on PC.Results:The process and analysis could be performed successfully on PC.The cerebral perfusion mapping provided valuable hemodynamic information and showed the extent of perfusion disturbances.Conclusion:PC aided mapping of MR cerebral perfusion weighted imaging [JP2]is a simple and accessible technique for delineating the hemodynamic abnormalities.The methods could obtain more diagnostic information,and has great practical value in both clinical and research workes.
Cerebral blood volume
Personal computer
Cite
Citations (0)
Perfusion refers to the flow of blood through the capillary network, which enables the transport of oxygen, nutrients, and waste to or from the tissues surrounding each capillary bed. Cerebral perfusion is the process by which blood transports oxygen and nutrients to the brain tissues, where they are utilized for various functions. This process is generally considered equivalent to the blood flow process in the brain. Cerebral perfusion imaging can provide information on cerebral hemodynamics at the level of the microvasculature and is therefore a valuable approach for identifying and monitoring the pathophysiological processes of neurological diseases. Perfusion MRI has been widely used for the evaluation of tumors, cerebrovascular diseases, and neurodegenerative diseases. Compared to nuclear medicine and computed tomography (CT) perfusion imaging studies, the greatest advantage of perfusion MRI is the absence of ionizing radiation, which allows repeat examinations within a short period of time without exposing patients to multiple doses of radiation. Current perfusion MRI techniques can be divided into two categories, based on the type of contrast agent used: (1) techniques involving the intravenous (IV) injection of an exogenous, non-diffusible contrast agent—gadopentetate dimeglumine—to induce dynamic changes in MRI signal intensity that are recorded and analyzed to obtain cerebral perfusion parameters, such as dynamic susceptibility contrast (DSC) and dynamic contrast-enhanced (DCE) imaging; and (2) techniques involving the use of water in the human body as an endogenous, diffusible contrast agent to perform imaging and obtain cerebral perfusion parameters, such as arterial spin labelling (ASL).
Dynamic Contrast-Enhanced MRI
Dynamic contrast
Cite
Citations (4)
Objective We compared cerebral blood flow (CBF) measured using computed tomographic (CT) perfusion (CTP) and N-isopropyl-p-[(123) I]-iodoamphetamine cerebral perfusion single-photon emission computed tomography (SPECT). Methods We used a 320-row area detector CT and N-isopropyl-p-[(123) I]-iodoamphetamine cerebral perfusion SPECT under similar conditions in patients with chronic cerebrovascular disease. Images were automatically aligned 3-dimensionally for voxel-by-voxel comparisons. Results Linear positive correlations were observed between CTP-CBF including high-blood-flow areas and SPECT-CBF over the whole brain (r = 0.001–0.6, P < 0.01), superior cerebral level (r = 0.45–0.93, P < 0.01), basal ganglia level (r = 0.44–0.77, P < 0.01), and skull base (r = 0.02–0.66, P < 0.01). Correlations between CTP-CBF excluding high-blood-flow areas were significantly higher (P < 0.0001). Conclusions Computed tomographic perfusion overestimated CBF compared with SPECT and showed poor correlation at the skull base. Computed tomographic perfusion CTP excluding high-blood-flow areas improved the correlation over the whole brain in patients with chronic cerebrovascular disease.
Iodine-123
Emission computed tomography
Cite
Citations (3)
This study was undertaken to determine the effects of different pH management strategies during retrograde cerebral perfusion on the relationship between retrograde perfusion pressure and brain tissue perfusion. Six pigs were subjected to an alpha-stat strategy and another 6 to a pH-stat strategy during hypothermic (15°C) retrograde cerebral perfusion at perfusion pressures of 10 to 70 mm Hg, in increments of 10 mm Hg every 20 min. Regional cerebral blood flow was significantly higher in the pH-stat group than in the alpha-stat group. The cerebral blood flow peaked at perfusion pressures of 40–50 mm Hg (18.6% ± 10.8% in the pH-stat group vs. 3.6% ± 1.2% in the alpha-stat group). In both groups, the intracranial pressure remained below the critical level of 25 mm Hg, even at a retrograde perfusion pressure of 70 mm Hg. Cerebral lactate production was higher in the alpha-stat group than the pH-stat group during retrograde cerebral perfusion at pressures of 10–30 mm Hg. Compared to the alpha-stat strategy, the pH-stat strategy significantly improved brain tissue perfusion. With an open inferior vena cava, the optimal perfusion pressure seems to be 40–50 mm Hg.
Cite
Citations (2)
Subarachnoid haemorrhage
Cerebral Hypoperfusion
Cerebrovascular Circulation
Cite
Citations (0)
The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation x 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current.
Image noise
Cite
Citations (23)
Perfusion CT studies of regional cerebral blood flow (rCBF), involving sequential acquisition of cerebral CT sections during IV contrast material administration, have classically been reported to be achieved at 120 kVp. We hypothesized that using 80 kVp should result in the same image quality while significantly lowering the patient's radiation dose, and we evaluated this assumption. In five patients undergoing cerebral CT survey, one section level was imaged at 120 kVp and 80 kVp, before and after IV administration of iodinated contrast material. These four cerebral CT sections obtained in each patient were analyzed with special interest to contrast, noise, and radiation dose. Contrast enhancement at 80 kVp is significantly increased (P < .001), as well as contrast between gray matter and white matter after contrast enhancement (P < .001). Mean noise at 80 kVp is not statistically different (P = .042). Finally, performance of perfusion CT studies at 80 kVp, keeping mAs constant, lowers the radiation dose by a factor of 2.8. We, thus, conclude that 80 kVp acquisition of perfusion CT studies of rCBF will result in increased contrast enhancement and should improve rCBF analysis, with a reduced patient's irradiation.
Iodinated contrast
Contrast Enhancement
Cite
Citations (252)
Purpose: The purpose of this work was to investigate the validity of perfusion MRI in comparison with stable xenon CT for evaluating regional cerebral blood flow (rCBF). Method: The rCBF was measured by xenon CT and perfusion MRI within a 24 h interval in 10 patients (mean ± SD age 63 ± 10 years). For perfusion MRI, absolute values of rCBF were calculated based on the indicator dilution theory after injection of 0.1 mmol/kg of Gd-DTPA. Eight to 10 regions of interest (37 mm2) were located in the white and gray matter on the rCBF images for each of the 10 patients. Results: The mean ± SD values of rCBF in gray matter were 48.5 ± 14.1 ml/100 g/min measured by xenon CT and 52.2 ± 16.4 ml/100 g/min measured by perfusion MRI. In the white matter, the rCBF was 22.6 ± 9.1 ml/100 g/min by xenon CT and 27.4 ± 6.8 ml/100 g/min by perfusion MRI. There was a good correlation of rCBF values between perfusion MRI and xenon CT (Pearson correlation coefficient 0.83; p < 0.0001). Conclusion: Comparable to xenon CT, perfusion MRI provides relatively high resolution, quantitative local rCBF information coupled to MR anatomy.
Cerebrovascular Circulation
Cite
Citations (63)
PURPOSE: To determine the value of perfusion computed tomography (CT) in a clinical study of patients with stroke and compare the results with single photon emission CT (SPECT) findings. MATERIALS AND METHODS: Perfusion CT was performed within 6 hours of symptom onset in 32 patients with possible stroke. Cerebral blood volume (CBV), cerebral blood flow (CBF), and time to peak contrast material enhancement were calculated on the basis of the CT results. Cerebral SPECT was also performed in a subgroup of 18 patients. Perfusion CT and SPECT findings were compared in a lesion-by-lesion analysis. Perfusion CT results were compared with follow-up CT and magnetic resonance imaging findings. RESULTS: Areas of reduced CBF were detected with the aid of perfusion CT in 25 of 28 patients with a proved infarct (sensitivity, 89%). The results of the CBF maps corresponded well to SPECT findings in 13 (81%) of 16 patients, but ischemia was located outside the scanning level in the other three patients and was therefore missed. Perfusion CT revealed various changes in CBF, CBV, and time to peak enhancement in ischemic territories. CONCLUSION: Perfusion CT not only allows early detection of cerebral ischemia but also yields valuable information about the extent of perfusion disturbances.
Stroke
Emission computed tomography
Cite
Citations (325)
Objective:To preliminarily evaluate the feasibility and potential values of whole-brain perfusion imaging performed with 256-slice CT to assess normal adult cerebral hemodynamics.Methods: Thirty-five normal results were selected from one hundred and fourteen patients who underwent brain CT unenhanced scan,CT perfusion imaging and CT angiography in head and neck for suspicion of ischemic cerebrovascular disease.The radiation dosage of CT perfusion imaging was recorded.Two senior neuroradiologic doctors independently analyzed the CT perfusion maps.Region of interest(ROI) was placed on bilateral temporal gray matter of two slices(the basal ganglia slice and body of lateral cerebral ventricle slice) supplied by middle cerebral artery,and the cerebral blood flow(CBF),cerebral blood volume(CBV),mean transiting time(MTT) and time to peak(TTP) values of ROI were automatically calculated by CT perfusion software.The mean values of perfusion parameters were compared by one-way ANOVA test.Results: The radiation dosage of thirty-five normal adults was 2.307 ± 0.008 mSv.There were no statistically significant differences between the two observers on the mean values of perfusion parameters(P 0.05).The CBV and CBF values of the two observers between two slices had statistically differences(P 0.05).Conclusion: With the lower radiation dosage and the stable and reproducible perfusion parameters,whole-brain perfusion imaging performed with 256-slice CT can be used to assess the entire cerebral hemodynamics.
Cite
Citations (0)