Computed Tomogram Angiography, CTA

Transcription

1 Chin J Radiol 2002; 27: [1] 4.8% 2.6% 42.2% Sahs [2] 48 20% 40% 67% 2% 5% [3] 20% [4] 10% 15% 41% 48% [5] [6] Computed Tomogram Angiography,

2 202 Subtraction Angiography (DSA) [7] Digital 8mm CT Picker PQ2000 CT Elsint Twin FLASH CT nonionic iodinized contrast medium 18 CT 1:2.5 pitch 2mm CT l0mm 2mm 60-80mm Sylvian fissure Sylvian 85 5 Picker PQ2000 spiral CT 87 3 Elsint Twin FLASH spiral CT source images Picker PQ2000 CT Voxel Q Elsint Silicon Graphy 2 surface shaded display (SSD) 4 maximal intensity projection (MIP) 5 1 CT for Windows SPSS 8.0 Microsoft ACCESS PC SPSS 8.0

3 203 Maximal Intensity Projection (MIP) Surface Shaded Display (SSD) 103 CT DSA CT- 95 Sensitivity Specificity Positive predictive value Negative predictive value CT-

4 204 [17] Bifurcation of MCA(13), ACoA(12),ICA of PCoA orifice(33), Distal A1(3), M1 of MCA(2), Proximal A2(1), ICA(4), Tip of basilar artery(2), PCA(3), Vertebral artery(1)

5 CT 95 CT 62 Positive predictive value Sensitivity Specificity Negative predictive value Positive predictive value Sensitivity Negative predictive value Specificity 11a DSA 11b

6 Dilatation of the tip of basilar artery 1 DSA 11 SSD 12 2 DSA %(68/74) 85.7% (24/24+4) [7] 4 high-attenuation blood clot motion artifacts vascular loops infundibulum of the posterior communicating artery [8] [8] a 12b SSD 13a 13b

7 207 14a 14b 15a 15b DSA M2 SSD SDH DSA M2 SSD SDH 15 1 M1 M2 12 mm 16a CT sylvian fissure 16b DSA 6 mm DSA 17a reconstruction MPR outside the imaging volume 17b closing to the skull base

8 208 16a 16b M 1 M 2 12 mm CT Sylvian fissure 17a 17b DSA 6 mm MPR difficult to identify against the bony background cavernous portion of the internal carotid artery in the positive predictive value negative predictive value [9]

9 209 18a 18b MIP MIP SSD 19a 19b CT DSA [10] IV line injector 90% (1) Shaded surface display, SSD (2)

10 210 20a 20b CT DSA scan CT number Maximal intensity projection, MIP CT DSA (3) Multiple Planer reconstruction, MPR Curved planer reconstruction, CPR (4) Multiple threshold display inner view SSD MIP SSD 3D MIP [11] MIP SSD MIP a,b 3D [7,9,11~21] CT spiral 3ml 350mg% Omnipaque 370mg% Ultravist 80ml 18 CT CT 2mm [8]

11 CT MRA DSA [21~23] 0.1%-2.6% morbidity 1. MRA [6,24~26] MRA 2. [6] overlapping artifact [9] 4. Gholkar et al mgy [9] MRA MRA Sahs. Intracranial aneurysm and subarachnoid hemorrhage: a cooperative study, Philadelphia, Lippincott 1969: Sekhax LN, Heros RC. Origin, growth & rupture of sacular aneurysms-a review. Neurosurgery 1981; 70: McCormick WF. Sacular intracranial aneurysms-an autopsy study. J Neurosurg 1965; 22: Locksley HB. Natural history of subarachnoid hemorrhage: J Neurosurg 1966; 25: ; 10; Hope KA. Three-dimension CT angiography in the detection and characterization of intracranial berry aneurysms. AJNR 1997; 17: Teasdale E, Stotham P, Straiton J, et al. Non-invasive radiological investigation for oculomotor palsy. Neurosurg Psychiatry 1990; 53: Aoki S, Sasaki Y, Machida T, et al. Cerebral aneurysms: detection and delineation using 3-D CT angiography. AJNR 1992; 12: Newell DW, LeRoux PD, Dacey RG, et al. CT infusion scanning for the detection of cerebral aneurysms. J Neurosurg 1989; 71: Rieger J, Hosten N, Neumann K, et al. Initial clinical experience with spiral CT and 3D arterial reconstruction in intracranial aneurysms and arteriovenous malformation. Neuroradiology 1996; 38: Schwartz RB, Tice HM, Hooten SM, et al. Evaluation of cerebral aneurysms with helical CT: correlation with conventional angiography and MR angiography. Radiology 1994; 192: Katz DA, Marks MP, Napel SA, Bracci PM, Roberta SL. Circle of Willis: evaluation with spiral CT angiography, MR angiography and conventional angiography. Radiology 1995; l95: Albenco RA, Patel M, Casey S, Jacobs B, Maguire W, DeckerR. Evaluation of the circle of Willis with threedimensional CT angiography in patients with suspected intracranial aneurysms. AJNR 1995; l6: l Tampieri D, Leblanc R, Oleszek J, et al. Three dimensional computed tomographic angiography of cerebral aneurysms. Neurosurgery 1995; 36: Wang LS, Lam WWM, Liang E, Huang YN, Chan YL, Kay R. Variability of magnetic resonance angiography and computed tomography angiography in grading middle artery stenosis. Stroke 1996; 27: Ogawa T, Okudera T, Noguchi K, et al. Cerebral aneurysms: evaluation with three dimensional CT angiography. AJNR 1996; 17: Knauth M, von Kummer R, Jansen O, Hahnei S. Dorfler A, Sartor K. Potential of CT angiography in acute ischemic stroke. AJNR 1997; 18:

12 Shrier DA, Tanaka H, Numaguchi Y, Konno S, Patel U, Shibata D. CT angiography in the evaluation of acute stroke. AJNR 1997; 18: Ng SH, Wong HF, Ko SF, Lee CM, Yen PS, Wai Y, et al. CT angiography of intracranial aneurysms: advantages and pitfalls. Eur J Radiol 1997; 25: Caplan LR, Pessin MS. Symptomatic carotid artery disease and carotid endarterectomy. Ann Rev Med 1988; 39: Farnest F, Forbe s G, Sandok BA, et al. Complications of cerebral angiography: prospective assessment of risk. AJR 1984; 142: O Leary DH. Mattle H, Potter JE. Atheromatous pseudo-occlusion of the internal carotid artery. Stroke 1989; 20: Palmer FJ. The RACR survey of intravenous contrast media reactions final report. Australia Radiol 1988; 32: Katayama H, Yamaguchi K, Kozuka T, et al. Adverse reactions to ionic and nonionic contrast media: a report from the Japanese committee on the safety of contrast media. Radiology 1990; 175: Schrott KM, Behrends B, Ciauss W, et al. Low-osmolality contrast media: premises and promises. Radiology l987; 162: 1-8

13 213 Three dimensional CT angiography in the detection of intracranial aneurysms KUEI-LI LIN 1,2,3 WU-CHUNG SHEN 1,2 Department of Radiology 1, China Medical College Hospital; School of Medicine 2, China Medical College Department of Radiation Oncology 3, Chimei Medical Center The purposes of this study are, first, to evaluate the diagnosis sensitivity and specificity of in intracranial arterial aneurysm and, second, to assess the advantages and pitfalls of its role as the first-line diagnostic tool for spontaneous SAH and for the patients suspected of having intracranial aneurysm due to other symptoms. During the period form May 1996 to June 1999, we performed with MIP and SSD for 103 patients with suspicion of intracranial aneurysm. We analyzed the presence and morphology of any aneurysms. DSA or surgery acted as the control. 95 patients were eligible for analysis. (Mean age, 56.8 years; range, 23 to 86 years). 74 aneurysms were found in 66 patients. Negative findings at angiography were noted in 7 patients. Sensitivity and specificity of 3-D for all patients and all aneurysm were 93.9% and 89.6%, 91.8% and 85.7%, respectively. with its high sensitivity and specificity for aneurysms can compliment conventional catheter angiography for its better demonstration of the 3-D anatomy. It can provide surgical information about the shape, neck, direction of aneurysms, and adjacent vascular and bone structures. can be the first-line screening tool for SAH routinely. with its high sensitivity and specificity for all patients may be useful in the follow-up of untreated aneurysms and at-risk groups due to its less invasive and less expensive. But if radiation is essential, MRA is the alternative. Recognition of the limitations of CT angiography is important in minimizing interpretation errors. Key words: computed tomography; angiography; brain, aneurysm