Effects of Increased Image Noise on Image Quality and Quantitative Interpretation in Brain CT Perfusion

Overview

Journal AJNR Am J Neuroradiol

Specialty Neurology

Date 2013 Apr 6

PMID 23557960

Citations 12

Authors

K Juluru

J C Shih

A Raj

J P Comunale

H Delaney

E D Greenberg

C Hermann

Y B Liu

A Hoelscher

N Al-Khori

P C Sanelli

Affiliations

Soon will be listed here.

Abstract

Background And Purpose: There is a desire within many institutions to reduce the radiation dose in CTP examinations. The purpose of this study was to simulate dose reduction through the addition of noise in brain CT perfusion examinations and to determine the subsequent effects on quality and quantitative interpretation.

Materials And Methods: A total of 22 consecutive reference CTP scans were identified from an institutional review board-approved prospective clinical trial, all performed at 80 keV and 190 mAs. Lower-dose scans at 188, 177, 167, 127, and 44 mAs were generated through the addition of spatially correlated noise to the reference scans. A standard software package was used to generate CBF, CBV, and MTT maps. Six blinded radiologists determined quality scores of simulated scans on a Likert scale. Quantitative differences were calculated.

Results: For qualitative analysis, the correlation coefficients for CBF (-0.34; P < .0001), CBV (-0.35; P < .0001), and MTT (-0.44; P < .0001) were statistically significant. Interobserver agreements in quality for the simulated 188-, 177-, 167-, 127-, and 44-mAs scans for CBF were 0.95, 0.98, 0.98, 0.95, and 0.52, respectively. Interobserver agreements in quality for the simulated CBV were 1, 1, 1, 1, and 0.83, respectively. For MTT, the interobserver agreements were 0.83, 0.86, 0.88, 0.74, and 0.05, respectively. For quantitative analysis, only the lowest simulated dose of 44 mAs showed statistically significant differences from the reference scan values for CBF (-1.8; P = .04), CBV (0.07; P < .0001), and MTT (0.46; P < .0001).

Conclusions: From a reference CTP study performed at 80 keV and 190 mAs, this simulation study demonstrates the potential of a 33% reduction in tube current and dose while maintaining image quality and quantitative interpretations. This work can be used to inform future studies by using true, nonsimulated scans.

Citing Articles

Radiation dose in CT-based active surveillance of small renal masses may be reduced by 75%: A retrospective exploratory multiobserver study.

Borgbjerg J, Larsen N, Salte I, Gronli N, Klaestrup E, Negard A Res Diagn Interv Imaging. 2024; 5:100019.

PMID: 39076165 PMC: 11265490. DOI: 10.1016/j.redii.2022.100019.

An automated technique for global noise level measurement in CT image with a conjunction of image gradient.

Kuo H, Mahmood U, Kirov A, Mechalakos J, Biancia C, Cervino L Phys Med Biol. 2024; 69(9).

PMID: 38537310 PMC: 11608062. DOI: 10.1088/1361-6560/ad3883.

Dataset on renal tumor diameter assessment by multiple observers in normal-dose and low-dose CT.

Borgbjerg J, Larsen N, Salte I, Gronli N, Klaestrup E, Negard A Data Brief. 2023; 51:109672.

PMID: 37965591 PMC: 10641580. DOI: 10.1016/j.dib.2023.109672.

Impact of Noise Level on the Accuracy of Automated Measurement of CT Number Linearity on ACR CT and Computational Phantoms.

Anam C, Amilia R, Naufal A, Sutanto H, Dwihapsari Y, Fujibuchi T J Biomed Phys Eng. 2023; 13(4):353-362.

PMID: 37609515 PMC: 10440409. DOI: 10.31661/jbpe.v0i0.2302-1599.

Cerebral CT Perfusion in Acute Stroke: The Effect of Lowering the Tube Load and Sampling Rate on the Reproducibility of Parametric Maps.

Ioannidis G, Christensen S, Nikiforaki K, Trivizakis E, Perisinakis K, Hatzidakis A Diagnostics (Basel). 2021; 11(6).

PMID: 34205442 PMC: 8235517. DOI: 10.3390/diagnostics11061121.

References

Mayo J, Hartman T, Lee K, Primack S, Vedal S, Muller N . CT of the chest: minimal tube current required for good image quality with the least radiation dose. AJR Am J Roentgenol. 1995; 164(3):603-7. DOI: 10.2214/ajr.164.3.7863879. View

Saito N, Kudo K, Sasaki T, Uesugi M, Koshino K, Miyamoto M . Realization of reliable cerebral-blood-flow maps from low-dose CT perfusion images by statistical noise reduction using nonlinear diffusion filtering. Radiol Phys Technol. 2010; 1(1):62-74. DOI: 10.1007/s12194-007-0009-7. View

Wintermark M, Ko N, Smith W, Liu S, Higashida R, Dillon W . Vasospasm after subarachnoid hemorrhage: utility of perfusion CT and CT angiography on diagnosis and management. AJNR Am J Neuroradiol. 2006; 27(1):26-34. PMC: 7976085. View

Loftus M, Minkowitz S, Tsiouris A, Min R, Sanelli P . Utilization guidelines for reducing radiation exposure in the evaluation of aneurysmal subarachnoid hemorrhage: A practice quality improvement project. AJR Am J Roentgenol. 2010; 195(1):176-80. PMC: 3130505. DOI: 10.2214/AJR.09.3786. View

Smith A, Dillon W, Gould R, Wintermark M . Radiation dose-reduction strategies for neuroradiology CT protocols. AJNR Am J Neuroradiol. 2007; 28(9):1628-32. PMC: 8134195. DOI: 10.3174/ajnr.A0814. View

Konstas A, Wintermark M, Lev M . CT perfusion imaging in acute stroke. Neuroimaging Clin N Am. 2011; 21(2):215-38, ix. DOI: 10.1016/j.nic.2011.01.008. View

Sanelli P, Jou A, Gold R, Reichman M, Greenberg E, John M . Using CT perfusion during the early baseline period in aneurysmal subarachnoid hemorrhage to assess for development of vasospasm. Neuroradiology. 2010; 53(6):425-34. PMC: 3118045. DOI: 10.1007/s00234-010-0752-z. View

Ding B, Ling H, Chen K, Jiang H, Zhu Y . Comparison of cerebral blood volume and permeability in preoperative grading of intracranial glioma using CT perfusion imaging. Neuroradiology. 2006; 48(10):773-81. DOI: 10.1007/s00234-006-0120-1. View

Turk A, Magarik J, Chaudry I, Turner R, Nicholas J, Holmstedt C . CT perfusion-guided patient selection for endovascular treatment of acute ischemic stroke is safe and effective. J Neurointerv Surg. 2011; 4(4):261-5. DOI: 10.1136/neurintsurg-2011-010067. View

10.

Krissak R, Mistretta C, Henzler T, Chatzikonstantinou A, Scharf J, Schoenberg S . Noise reduction and image quality improvement of low dose and ultra low dose brain perfusion CT by HYPR-LR processing. PLoS One. 2011; 6(2):e17098. PMC: 3037968. DOI: 10.1371/journal.pone.0017098. View

11.

Fainardi E, Di Biase F, Borrelli M, Saletti A, Cavallo M, Sarubbo S . Potential role of CT perfusion parameters in the identification of solitary intra-axial brain tumor grading. Acta Neurochir Suppl. 2009; 106:283-7. DOI: 10.1007/978-3-211-98811-4_53. View

12.

Provenzale J, Shah K, Patel U, McCrory D . Systematic review of CT and MR perfusion imaging for assessment of acute cerebrovascular disease. AJNR Am J Neuroradiol. 2008; 29(8):1476-82. PMC: 8119039. DOI: 10.3174/ajnr.A1161. View

13.

Britten A, Crotty M, Kiremidjian H, Grundy A, Adam E . The addition of computer simulated noise to investigate radiation dose and image quality in images with spatial correlation of statistical noise: an example application to X-ray CT of the brain. Br J Radiol. 2004; 77(916):323-8. DOI: 10.1259/bjr/78576048. View

14.

Wintermark M, Smith W, Ko N, Quist M, Schnyder P, Dillon W . Dynamic perfusion CT: optimizing the temporal resolution and contrast volume for calculation of perfusion CT parameters in stroke patients. AJNR Am J Neuroradiol. 2004; 25(5):720-9. PMC: 7974477. View

15.

Sergides I, Hussain Z, Naik S, Good C, Miles K, Critchley G . Utilization of dynamic CT perfusion in the study of intracranial meningiomas and their surrounding tissue. Neurol Res. 2009; 31(1):84-9. DOI: 10.1179/174313208X331563. View

16.

Sanelli P, Ugorec I, Johnson C, Tan J, Segal A, Fink M . Using quantitative CT perfusion for evaluation of delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage. AJNR Am J Neuroradiol. 2011; 32(11):2047-53. PMC: 3237788. DOI: 10.3174/ajnr.A2693. View

17.

Wintermark M, Maeder P, Thiran J, Schnyder P, Meuli R . Quantitative assessment of regional cerebral blood flows by perfusion CT studies at low injection rates: a critical review of the underlying theoretical models. Eur Radiol. 2001; 11(7):1220-30. DOI: 10.1007/s003300000707. View

18.

Sanelli P, Lev M, Eastwood J, Gonzalez R, Lee T . The effect of varying user-selected input parameters on quantitative values in CT perfusion maps. Acad Radiol. 2004; 11(10):1085-92. DOI: 10.1016/j.acra.2004.07.002. View

19.

Ramli N, Rahmat K, Mah E, Waran V, Tan L, Chong H . Use of permeability surface area-product to differentiate intracranial tumours from abscess. Biomed Imaging Interv J. 2011; 5(1):e6. PMC: 3097750. DOI: 10.2349/biij.5.1.e6. View

20.

Suzuki K, Morita S, Masukawa A, Machida H, Ueno E . Utility of CT perfusion with 64-row multi-detector CT for acute ischemic brain stroke. Emerg Radiol. 2010; 18(2):95-101. DOI: 10.1007/s10140-010-0905-8. View