Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
The Imaging
Pathway
for
TIA
Iris C, Sarah C, Sharon D, Janine E, Sam F,
Jessica K, Andrea K, Andrew N, George S, Phuong T
...
What is a TIA?
A brief episode of neurological dysfunction caused
by focal brain or retinal ischemia (loss of blood
flow),...
The Imaging Pathway
Transient Ischaemic Attack (TIA)
Cranial CT
Carotid Doppler Ultrasound
Normal 30-70% stenosis +/-
“non-surgical” plaque
En...
Transient Ischaemic Attack (TIA)
Cranial CT
What is Cranial CT and what role does it play
in TIA imaging?
What is Cranial ...
Do you agree with its position in the imaging
pathway?
Cranial CT should be the initial imaging modality
in diagnosing TIA...
Transient Ischaemic Attack (TIA)
Cranial CT
Carotid Doppler Ultrasound
Normal 30-70% stenosis +/-
“non-surgical” plaque
En...
Transient Ischaemic Attack (TIA)
Cranial CT
Carotid Doppler Ultrasound
What is Carotid Doppler and what role does
it play ...
Sensitivity and Specificity
[Wardlaw et al 2006]{Wardlaw, 2006 #75}
0-49%
stenosis
50-69%
stenosis
> 70-99%
stenosis
Carot...
Transient Ischaemic Attack (TIA)
Cranial CT
Carotid Doppler Ultrasound
Normal 30-70% stenosis +/-
“non-surgical” plaque
En...
Transient Ischaemic Attack (TIA)
Cranial CT
Carotid Doppler Ultrasound
Normal
Look for other sources of emboli
-Echocardio...
Transient Ischaemic Attack (TIA)
Cranial CT
Carotid Doppler Ultrasound
30-70% stenosis +/-
“non-surgical” plaque
MRA
Medic...
MRA
What is MRA and what role does it play in
TIA imaging?
What is MRA?
Magnetic Resonance Angiography (MRA) uses magnetic...
Statistics:
MRA has a sensitivity of 92% and specificity of 76% in
the detection of extracranial carotid disease [Easton, ...
Advantages Limitations
- “…widely available noninvasive
technique that requires no
radiation exposure and no
administratio...
> 30%
stenosis
> 70%
stenosis
> 70-99%
stenosis
US 93% SE
82% SP
93% SE
92% SP
89% SE
93% SP
MRA 89% SE
82% SP
90% SE
95% ...
Transient Ischaemic Attack (TIA)
Cranial CT
Carotid Doppler Ultrasound
Normal 30-70% stenosis +/-
“non-surgical” plaque
En...
Transient Ischaemic Attack (TIA)
Cranial CT
Carotid Doppler Ultrasound
EndarterectomyAngioplasty
± stent
> 70% stenosis on...
MRA or CTA
Indications for CTA: Patients with suspected carotid
artery disease such as occlusion, stenosis and
aneurysms
T...
Advantages Disadvantages
More widely available
than MRI
Risks associated with us
of iodinated contrast
Less susceptible to...
Transient Ischaemic Attack (TIA)
Cranial CT
Carotid Doppler Ultrasound
Normal 30-70% stenosis +/-
“non-surgical” plaque
En...
EndarterectomyAngioplasty
± stent
MRA
Medical Treatment
MRA or CTA
Tests incongruent
Further non-invasive imaging
(do alte...
MRAMRA or CTA
Tests incongruent
Further non-invasive imaging
(do alternate test)
MRA, CTA or DSA
Further non-invasive imaging
(do alternate test)
MRA, CTA or DSA
What is DSA and what role does it play in TIA
imaging?
In...
Advantages of
DSA
Advantages of
Conventional Arteriography
• Decreased morbidity
• Decreased patient discomfort
• Decrease...
CTA MRA DUS
Sensitivity 0.65 1.0 0.85
Specificity 1.0 0.57 0.71
Recommendations for further research: DSA assumed as gold
...
MRAMRA or CTA
Tests incongruent
Further non-invasive imaging
(do alternate test)
MRA, CTA or DSA
MRAMRA or CTA
Tests incongruent
Further non-invasive imaging
(do alternate test)
MRA, CTA or DSA
< 70% stenosis> 70% steno...
EndarterectomyAngioplasty
± stent
MRA
Medical Treatment
MRA or CTA
Tests incongruent
Further non-invasive imaging
(do alte...
EndarterectomyAngioplasty
± stent
Carotid Angioplasty +/- Stent (CAS) and Endarterectomy (CEA)
CEA and CAS  reduce and pr...
Conclusion
Imaging TIA to determine degree of stenosis  medical/surgical intervention
 decrease stroke recurrence
Crania...
References
• Anderson, G., et al. (2000) CT angiography for the detection and characterization of carotid artery bifurcati...
References
• Gaitini, D., Soudak, M. (2005) "Diagnosing Carotid Stenosis on Doppler imaging". The Journal of Ultrasound in...
References
• Patel, S., Collie, D., Wardlaw, J., Lewis, S., Wright, A., Gibson, R., Sellar, R. (2002) Outcome, observer re...
References
• Willinek, W., von Falkenhausen, M., Born, M., Gieseke, J., Holler, T., Klockgether, T.,Textor,H., Schild, H.,...
Thank you
for listening!
Upcoming SlideShare
Loading in …5
×

Transient Ischaemic Attack - Imaging Pathways

2,258 views

Published on

This is a group powerpoint presentation that I created for our university assignment - it explores the imaging pathways a worker in the medical imaging department would take with a patient suffering from a Transient Ischaemic Attack (TIA).

Published in: Education

Transient Ischaemic Attack - Imaging Pathways

  1. 1. The Imaging Pathway for TIA Iris C, Sarah C, Sharon D, Janine E, Sam F, Jessica K, Andrea K, Andrew N, George S, Phuong T Transient Ischaemic Attacks
  2. 2. What is a TIA? A brief episode of neurological dysfunction caused by focal brain or retinal ischemia (loss of blood flow), with clinical symptoms lasting less than one hour, and without evidence of acute infarction. [Solenski, 2004] Statistics Transient ischemic attacks is an indicator for internal carotid arteries imaging, as there is a significantly increased risk of stroke [Jaff, et al., 2008]. It has been estimated that 4-20% of patients will have a stroke within the 90 days after the first TIA and 1/2 within the first 2 days. [Bonifati, et al., 2011] Why is imaging important? TIA increases a patient’s risk of developing a stroke, therefore proper diagnosis and treatment is urgently required to reduce and prevent the risk of stroke recurrence, otherwise permanent brain injury, disability and even death may result. Types of Imaging There are a number of diagnostic imaging tests available: Cranial CT, CTA (CT angiography), MRA (MR angiography), DSA (digital subtraction angiography) and Doppler ultrasound.
  3. 3. The Imaging Pathway
  4. 4. Transient Ischaemic Attack (TIA) Cranial CT Carotid Doppler Ultrasound Normal 30-70% stenosis +/- “non-surgical” plaque EndarterectomyAngioplasty ± stent Look for other sources of emboli -Echocardiogram -Holter monitor MRA Tests congruent Medical Treatment > 70% stenosis on appropriate side MRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA < 70% stenosis> 70% stenosis Tests congruent
  5. 5. Transient Ischaemic Attack (TIA) Cranial CT What is Cranial CT and what role does it play in TIA imaging? What is Cranial CT? Cross-sectional images of the brain in sagittal, axial and coronal planes via ionising radiation Indications for Cranial CT: • Known bleeding tendency • Deteriorating level of consciousness • Unexplained progressive / fluctuating symptoms • Papilloedema due to increased ICH • Neck stiffness • Fever or severe headache • Head injury (risk of subdural haematoma) [Solenski, N.J., 2004 ] What is its role in diagnosis? • The initial imaging modality of choice • Detects intracranial bleeding, such as subdural haematoma, intra-cerebral haemorrhage or tumour mass • Detects cerebral infarction appropriate to TIA symptoms in 15-30% of patients [Culebras, A., et.al 1997] Technique: • Contrast is not initially used because “there is a theoretical concern about promoting cerebral ‘toxicity’” [Culebras, A., 1997] – it may disrupt the blood-brain barrier in large infarcts • If symptoms persist after 2 to 3 weeks, it is recommended to have contrast as the “fogging effect” may obscure the possibility of demonstrating infarction [Culebras, A., 1997]
  6. 6. Do you agree with its position in the imaging pathway? Cranial CT should be the initial imaging modality in diagnosing TIA because of its: • Speed • Ability to exclude other brain pathology, especially intracerebral haemorrhage as a cause of TIA • Wide availability • Clinician familiarity with the procedure [Smith, W.S., 2003] Cranial CT excludes ICH (near 100% sensitivity) and subarachnoid haemorrhage (96% sensitivity) or subdural haematoma. [Culebras, A., 1997] CT can also detect silent infarctions (contains no previous history) in 13% of cases and 47% of patients with TIA and known carotid stenosis. [Culebras, A., 1997] Limitations of Cranial CT? • No abnormalities are detected on the CT scan in early cases of infarction (1-4 hours), but cases of haemorrhagic infarction and massive MCA territory infarctions are more detectable [Culebras, A., 1997] • Due to increase bony artefact in the posterior fossa, MRI is the preferred study over CT to evaluate disease in the brainstem or cerebellum [Tidy, C., 2010] • Despite a normal appearance on a CT scan, an additional CT scan is required after 24 hours following the onset of stroke symptoms • Pregnancy is a contraindication [Tidy, C., 2010] Due to these limitations, other modalities such as Carotid Doppler Ultrasound are required to correctly diagnose TIA. After five hours of acute onset of symptoms, cerebral infarction is indicated as a hypodense area
  7. 7. Transient Ischaemic Attack (TIA) Cranial CT Carotid Doppler Ultrasound Normal 30-70% stenosis +/- “non-surgical” plaque EndarterectomyAngioplasty ± stent Look for other sources of emboli -Echocardiogram -Holter monitor MRA Tests congruent Medical Treatment > 70% stenosis on appropriate side MRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA < 70% stenosis> 70% stenosis Tests congruent
  8. 8. Transient Ischaemic Attack (TIA) Cranial CT Carotid Doppler Ultrasound What is Carotid Doppler and what role does it play in TIA imaging? What is Carotid Doppler? • Use of a high resolution linear array transducer to view the carotid artery • B-mode scan, Colour flow Doppler, Spectral Doppler velocities are employed when conducting the scan [Gaitini & Soudak 2005] What role does it play in TIA imaging? • 80% of ischemic events are caused by atherosclerotic disease, commonly occurring at the carotid bifurcation [Landwehr P et al 2001] • Stenoses can be identified and quantified quickly though Doppler which is used to measure blood flow velocity and turbulence and assists in the assessment of plaque morphology • The degree of stenosis of the internal carotid artery is the primary parameter used for deciding upon therapeutic approaches for the patient. [Gaitini & Soudak 2005]
  9. 9. Sensitivity and Specificity [Wardlaw et al 2006]{Wardlaw, 2006 #75} 0-49% stenosis 50-69% stenosis > 70-99% stenosis Carotid Doppler Ultrasound 83% SE 84% SP 36% SE 91% SP 89% SE 84% SP Do you agree with its position in the imaging pathway? • Carotid Doppler Ultrasound assesses both morphology and heamodynamic abnormalities quickly, easily, non-invasively and accurately • Doppler assessments are necessary in determining therapeutic approaches, which are dependent on the degree of stenosis found [Gaitini & Soudak 2005]. • Carotid stenosis >70% is a high risk factor for stroke and 50% of subsequent strokes occur within 2 days [Bonifati 2011]. Doppler allows physicians to determine the risk and monitor patients appropriately • MRA is identified as the imaging modality for <70% stenosis as MRA is more sensitive in categorising moderate ranges of stenosis [Anderson, Glenn B et al. 2000]. Advantages Disadvantages Non-invasive Heavy calcifications may cause shadowing and occlude information Cost effective Ultrasound probes cannot accurately examine carotid plaque under the mandible and the inter-cranial portion of the carotid artery (only useful for scanning along the patient’s neck) Accurate Dependent on operator skill Able to quickly diagnose Helps to determine potential risk of stroke Limitations of Carotid Doppler Ultrasound? • Doppler cannot always distinguish between severe and complete occlusion due to undetectable blood velocity • CTA AND MRA is indicated for patients with discrepant findings (e.g. with severe occlusion or atherosclerosis extending past the neck. ) [Gaitini & Soudak 2005]
  10. 10. Transient Ischaemic Attack (TIA) Cranial CT Carotid Doppler Ultrasound Normal 30-70% stenosis +/- “non-surgical” plaque EndarterectomyAngioplasty ± stent Look for other sources of emboli -Echocardiogram -Holter monitor MRA Tests congruent Medical Treatment > 70% stenosis on appropriate side MRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA < 70% stenosis> 70% stenosis Tests congruent
  11. 11. Transient Ischaemic Attack (TIA) Cranial CT Carotid Doppler Ultrasound Normal Look for other sources of emboli -Echocardiogram -Holter monitor
  12. 12. Transient Ischaemic Attack (TIA) Cranial CT Carotid Doppler Ultrasound 30-70% stenosis +/- “non-surgical” plaque MRA Medical Treatment Tests congruent
  13. 13. MRA What is MRA and what role does it play in TIA imaging? What is MRA? Magnetic Resonance Angiography (MRA) uses magnetic resonance techniques to evaluate extra- and intra-cranial vessels and any pathology such as stenosis and aneurysm. MRA is the manipulation of data series of the Time-of-flight of moving protons and the spin phase of protons and the magnetic field gradients. Technique: A magnetic field excites the protons in the brain’s tissue and the amount of signal released post-‘energy boost’ determines the different structures and tissues of the brain. Why MRA? In the early stages of TIA, MRA is able to identify the area of arterial occlusion [Muir, K., & Santosh, C., 2005]. The evidence of vessel occlusion by MRA has led to a “4- fold increased short-term risk of stroke”  earlier detection of stroke. [Easton, J. et. al, 2009] [Willinek, A. et. al, 2005]
  14. 14. Statistics: MRA has a sensitivity of 92% and specificity of 76% in the detection of extracranial carotid disease [Easton, J. et. al, 2009]. MRA can identify carotid plaques, the inflammation in the vessel and the stability of the plaque [Easton, J. et. al, 2009]. Intracranial MRA is 90% sensitive and specific [Clifton, A., 2000]. “Overall, the non-enhanced MRA showed sensitivity of 84.2% and specificity of 84.6%. The enhanced MRA showed sensitivity of 69.2 and specificity of 73.6.” [Tomanenk, A. et. al, 2006] A 2005 study: MRA has a 100% sensitivity stenosis and occlusions > 70% were correctly identified. [Willinek, A. et. al, 2005]. [Townsend, T. et. al, 2003]
  15. 15. Advantages Limitations - “…widely available noninvasive technique that requires no radiation exposure and no administration of contrast material.” [Bash, S. et. al, 2005] - Can be performed in conjunction with MRI - If contrast is injected, it shortens time of flight - “…requires comparatively long imaging times, frequently leading to patient motion artifacts and degradation of image quality.” [Bash, S. et. al, 2005] - Patients with pacemakers or severe claustrophobia - Non-enhanced MRA has a comparative lower spatial resolution than DSA and CTA [Bash, S. et. al, 2005] - Contrast induced images often overestimates the severity of stenosis in vessels [Townsend, T. et. al, 2003]
  16. 16. > 30% stenosis > 70% stenosis > 70-99% stenosis US 93% SE 82% SP 93% SE 92% SP 89% SE 93% SP MRA 89% SE 82% SP 90% SE 95% SP 86% SE 93% SP Is MRA justified in the flow chart? Do you agree or disagree with the chart?: The position is justified. MRA has a relative high sensitivity and specificity in regards to the detection of stenosis and occlusions as well as plaque, in the brain. From the table results, it is clear that the sensitivity and specificity of stenosis > 30% is relatively high  more sensitive modality for smaller stenoses. Improvements? Need for more current research for more definitive results of TIA in MRA. The imaging pathway does not account for the effect voxel size has on image quality. “...decreased voxel size improves the delineation of cervical carotid and vertebral arteries in MR angiograms” [Willinek, A et. al, 2005]. Need for alternative imaging? Patients with contraindications such as pacemakers, claustrophobia and patients whom are presented in the Emergency Room.
  17. 17. Transient Ischaemic Attack (TIA) Cranial CT Carotid Doppler Ultrasound Normal 30-70% stenosis +/- “non-surgical” plaque EndarterectomyAngioplasty ± stent Look for other sources of emboli -Echocardiogram -Holter monitor MRA Tests congruent Medical Treatment > 70% stenosis on appropriate side MRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA < 70% stenosis> 70% stenosis Tests congruent
  18. 18. Transient Ischaemic Attack (TIA) Cranial CT Carotid Doppler Ultrasound EndarterectomyAngioplasty ± stent > 70% stenosis on appropriate side MRA or CTA Tests congruent
  19. 19. MRA or CTA Indications for CTA: Patients with suspected carotid artery disease such as occlusion, stenosis and aneurysms Technique: Noncontrast CT of the head  Contrast CTA from the aortic arch through the circle of Willis Statistics? For >70% stenosis Sensitivity of CTA is 0.77 and specificity is 0.95 For patients with <70% stenosis Specificity is 0.67 and Specificity is 0.91 Why is CTA used? CTA is a quick, inexpensive and readily available way to assess stenosis in emergency patients after suspected TIA. What is CTA and what role does it play in TIA imaging?
  20. 20. Advantages Disadvantages More widely available than MRI Risks associated with us of iodinated contrast Less susceptible to artefacts as it uses digital subtraction techniques Only accurate to assess >70% stenosis or occlusions. Provides information about surrounding anatomy Allows for radiation exposure of radiosensitive tissues (thyroid, lenses) Faster scan time Is CTA justified in the flowchart? Do you agree or disagree with its position in the chart? CTA should be used as a non-invasive imaging technique for patients with >70% stenosis as it is fast and offers accurate results. [Koelemay, Nederkoorn, Reitsma, & Majoie, 2004] Need for alternative imaging? CTA has a high sensitivity and specificity rate for patients with >70% stenosism However it is less accurate for 50-69% stenosis of the carotid artery. Therefore other tests, such as MRA or DSA should be preformed on these patients. [Wardlaw, Chappell, Best, Wartolowska, & Berry, 2006] Recommendations for further research: High sensitivity of CTA for >70% stenonis More research is needed on the accuracy of CTA in detecting stenosis <70%. [Wardlaw, et al., 2006]
  21. 21. Transient Ischaemic Attack (TIA) Cranial CT Carotid Doppler Ultrasound Normal 30-70% stenosis +/- “non-surgical” plaque EndarterectomyAngioplasty ± stent Look for other sources of emboli -Echocardiogram -Holter monitor MRA Tests congruent Medical Treatment > 70% stenosis on appropriate side MRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA < 70% stenosis> 70% stenosis Tests congruent
  22. 22. EndarterectomyAngioplasty ± stent MRA Medical Treatment MRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA < 70% stenosis> 70% stenosis Tests congruent Tests congruent
  23. 23. MRAMRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA
  24. 24. Further non-invasive imaging (do alternate test) MRA, CTA or DSA What is DSA and what role does it play in TIA imaging? Indications for DSA: vascular abnormalities such as occlusion, stenosis and aneurysms, “suspected carotid dissection unconfirmed on non-invasive neuroimaging study, subarachnoid haemorrhage, intracerebral haemorrhage in the absence of hypertension, and vasculitis.” [Solenski, 2004] Technique: IV injection pre and post contrast digital imaging subtract precontrast images Statistics: A study by Chilcote, et al (1981) revealed that DSA had a sensitivity of 95%, specificity of 99% and accuracy of 97%. DSA sens 46%, spec 74% for detecting plaque ulceration [Streifler, et al 1994] Why is DSA considered gold standard? Superior spatial & contrast resolution (Jong et al, 2009), diagnosing severe (70- 90%) stenosis [Herzig, et al, 2004; Silvonnoinen, 2007], it is a dynamic study [Bash et. al, 2005] Limitations of DSA? Very invasive procedure, 0.7% risk of peri-procedural neurological injury [Joshi and Prabhakaran, 2010], 1% risk of stroke, 4% risk of TIA, and nearly a 1% mortality rate.” [Silvonnoinen, 2007] Figure 1. Still frames from an angiogram of carotid bifurcation in pt with ICA stenosis and stent placement
  25. 25. Advantages of DSA Advantages of Conventional Arteriography • Decreased morbidity • Decreased patient discomfort • Decreased hospitalisation time • Decreased procedure time • Decreased film cost • Increased contrast resolution • Usefulness in patients with limited arterial access • Lower cost per examination • Increased spatial resolution • Feasibility of selective injections • Less degradation of patient motion • Visualisation of small blood vessels Table: Comparative advantages of DSA and conventional arteriography. Retrieved from: http://www.princeton.edu/~ota/disk2/1985/8506/850605.PDF
  26. 26. CTA MRA DUS Sensitivity 0.65 1.0 0.85 Specificity 1.0 0.57 0.71 Recommendations for further research: DSA assumed as gold standard (reference)  no paper up-to-date that can evaluates the sensitivity and specificity of DSA alone. US CTA CTA+US Sensitivity 1.0 1.0 1.0 Specificity 0.75 0.844 0.844 Is DSA justified in the flowchart? Do you agree or disagree with the chart? The position is justified. Non- invasive imaging is the first line investigation for TIA. Need for alternative imaging? Alternative non-invasive imaging methods are available and widely used. • DUS, CTA and MRA all show similar accuracy in diagnosis of symptomatic carotid stenosis. No technique on its own is accurate enough to replace DSA.” [Patel, 2002] • “A recent review of literature suggests that a carefully planned approach using non-invasive imaging can replace invasive angiography for carotid artery assessment in a cost- effective and safe manner” [Jaff, 2008] Figure 1: Retrieved from Patel, 2002 Figure 2: Herzig, et al, 2004
  27. 27. MRAMRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA
  28. 28. MRAMRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA < 70% stenosis> 70% stenosis
  29. 29. EndarterectomyAngioplasty ± stent MRA Medical Treatment MRA or CTA Tests incongruent Further non-invasive imaging (do alternate test) MRA, CTA or DSA < 70% stenosis> 70% stenosis
  30. 30. EndarterectomyAngioplasty ± stent Carotid Angioplasty +/- Stent (CAS) and Endarterectomy (CEA) CEA and CAS  reduce and prevent embolic stroke recurrence/formation CEA CAS What is it? Invasive surgical removal of plaque through an incision of blood vessel Intra-arterial expansion using a balloon +/- stent Indications - ICA stenosis > 70%, surgically accessible stenosis, patient is stable, stenosis is symptomatic, rates of surgical complication <6% [Findlay, et al., 1997] - Suitable for high-risk patients who are not suitable for CEA Contraindications - Asymptomatic stenosis <60%, uncontrolled hypertension, diabetes, congestive heart failure, unstable angina or major neurological deficits [Findlay, et al., 1997] - Diabetes mellitus - >80 y.o. [Hobson, et al., 2004] - Ulceration of CA stenosis, >50% contralateral stenosis, echolucent plaque - Morphology increases risk of stroke in CAS, unfavourable anatomy [Maldonado, T., 2007] What type of imaging is involved? - Digital fluoroscopic imaging - Intraoperative Duplex US sens 100%, spec 100% [Wallaert, et al., 2011] - Angioscopy [Osman and Gibbons, 2001] - CT angiography sens and spec 90% - Transcranial Doppler Sonography + electroencephalography [Roh, et al, 2005] - Digital fluoroscopic imaging - Intraoperative Duplex US, C arm post- stent angiography [Branchereau, A. and Jacobs, M., 2005]
  31. 31. Conclusion Imaging TIA to determine degree of stenosis  medical/surgical intervention  decrease stroke recurrence Cranial CT is justified  initial imaging modality due to its speed, availability, accessibility, and ability to identify and exclude brain pathology. Stenosis > 70% : MRA + CT Angiography is justified. CTA  preferred over MRA, more readily available, inexpensive and fast for emergency patients. Carotid Doppler Ultrasound is quick, easy, relatively accurate, non-invasive and is able to identify degree of stenosis  justified as a compliment to CT. Stenosis 30-70%: MR Angiography is justified  suitable for plaque identification. Digital Subtraction Angiography (DSA) the "gold standard” BUT is fast being replaced by non-invasive imaging  last resort imaging
  32. 32. References • Anderson, G., et al. (2000) CT angiography for the detection and characterization of carotid artery bifurcation disease. Stroke 31.9: 2168-2174 • Bash, S. Villablanca, J.P., Jahan, R., Duckwiler, G., Tillis, M., Kidwell, C., Saver, J., Sayre, J. (2005) Intracranial vascular stenosis and occlusive disease: evaluation with CT angiography, MR angiography, and digital subtraction angiography. American Journal of Radiology, 26(5), 1012-1021. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/15891154 • Bisschops, R., Kappelle, L.J. , Mali, W., Van der Grond, J. (2002) Hemodynamic and Metabolic Changes in Transient Ischemic Attack Patients : A Magnetic Resonance Angiography and 1H-Magnetic Resonance Spectroscopy Study Performed Within 3 Days of Onset of a Transient Ischemic Attack. Journal of the American Heart Association, 33:110-115. Retrieved from http://stroke.ahajournals.org/content/33/1/110 • Bonifati, D., Lorenzi, A., Ermani, M., Refatti, F., Gremes, E., Boninsegna, C., Filipponi, S., Orrico, D. (2011). Carotid stenosis as predictor of stroke after transient ischemic attacks. Journal of Neurological Sciences, 303, pp. 85-89. Doi: 10.1016/j.jns.2011.01.005 • Chilcote, W., Modic, M., Pavilcek, W., Little, J., Furlan, A., Duchesneau, P., Weinstein, M. (1981). Digital Subtraction Angiography of the Carotid Arteries: A Comparative Study in 100 Patients. Radiology, 139: 287-295. Retrieved from http://radiology.rsna.org/content/139/2/287.long • Clifton, A. (2000). MR angiography. British Medical Bulletin, 56(2), 367-377. • Cloft, H., Joseph, G., Dion, J. (1999) Risk of Cerebral Angiography in Patients With SubarachnoidHemorrhage, Cerebral Aneurysm, and Arteriovenous Malformation : A Meta-Analysis. Journal of the American Heart Association, 30:317-320, Retrieved from http://stroke.ahajournals.org/content/30/2/317 • Culebras, A., Kase, C., Masdeu, J., Fox, A., Bryan, N., Grossman, C., Lee, D., Adams, H., Thies, W. (1997) Practice Guidlines for the Use of Imaging in Transient Ischemic Attacks and Acute Stroke. Ahajournals: Stroke; 28:1480 – 1497. Doi:10.1161/01.STR.28.7.1480 • Easton, J., Saver, J., Albers, G., Alberts, M., Chaturvedi, S., Feldmann, E., … Sacco, R. (2009). Definition and Evaluation of Transient Ischemic Attack: A Scientific Statement for Healthcare Professionals From the American Heart Association/American Stroke Association Stroke Council; Council on Cardiovascular Surgery and Anesthesia; Council on Cardiovascular Radiology and Intervention; Council on Cardiovascular Nursing; and the Interdisciplinary Council on Peripheral Vascular Disease: The American Academy of Neurology affirms the value of this statement as an educational tool for neurologists. Stroke, Journal of the American Heart Association, 40, 2276-2293. doi: 10.1161/STROKEAHA.108.192218 • Feldman, E., Cloft, H., Nguyen-Huynh, M., and McLaughlin, A. (2009). Vascular Imaging. In Jong, S., Louis, R., Caplan, K., Wong, K. (Ed.), Intracranial Atherosclerosis. Retrieved from http://books.google.com.au/books?id=cJ6hBWgF6X0C&pg=PA127&lpg=PA127&dq=why+is+dsa+gold+standard+for+TIA+imaging&source=bl&ots=- v_0r6WNvg&sig=Y-- blDJSulzozXhPULgHL8IvUN4&hl=en&sa=X&ei=AV6IUeyrDIydiAf_l4DoAg&ved=0CC0Q6AEwAA#v=onepage&q=why%20is%20dsa%20gold%20standar d%20for%20TIA%20imaging&f=false • Findlay, J., Tucker, W., Ferguson, G., Holness, R., Wallace, M., Wong, H. (1997) Guidelines for the use of carotid Endarterectomy: current recommendations from the Canadian Neurosurgical Society, Can Med Asso. 157: 653-659. Retrieved from http://www.cmaj.ca/content/157/6/653.full.pdf • Gaitini, D., Soudak, M. (2005) "Diagnosing Carotid Stenosis on Doppler imaging". The Journal of Ultrasound in Medicine. 24:1127–1136
  33. 33. References • Gaitini, D., Soudak, M. (2005) "Diagnosing Carotid Stenosis on Doppler imaging". The Journal of Ultrasound in Medicine. 24:1127–1136 • Grant, EG., Benson, C.B., Moneta, G.L., et al (2003). Carotid Artery Stenosis: Gray-scale and Doppler US diagnosis— Society of Radiologists in Ultrasound Consensus Conference. Radiology; 229:340– 346 • Herzig, R., Burval, S., Krupka, B., Vlachova, I., Urbanek, K., Mares, J. (2004) Comparison of ultrasonography, CT angiography and digital subtraction angiography in severe carotid stenosis. European Journal of Neurology, 11:774-781. Retrieved from http://www.upol.cz/fileadmin/user_upload/LF- kliniky/neurologie/Herzig_-_2004-6.pdf • Hirai, T., Korogi, Y., Ono, K., Nagano, M., Maruoka, K., Uemura, S., & Takahashi, M. (2002). Prospective evaluation of suspected stenoocclusive disease of the intracranial artery: combined MR angiography and CT angiography compared with digital subtraction angiography. American Journal of Radiology, 23(1), 93-101. Retrieved from http://www.ajnr.org/content/23/1/93.long • Hobson, R., Howard, V., Roubin, G., Brott, T., Ferguson, R., Pompa, J., Graham, D., Howard, G. (2004) Carotid artery stenting is associated with increased complications in octogenarians: 30 –day stroke and death r ates in the CREST lead-in phase., Journal of Vascular Surgery, Vol 40, No. 6, pp 1106-1111. Available from http://ac.els-cdn.com.ezproxy2.library.usyd.edu.au/S0741521404013059/1-s2.0-S0741521404013059-main.pdf?_tid=0978b716- b909-11e2-815d-00000aab0f6c&acdnat=1368146104_630dae0ea33715a932ccf403fb9b3d02 • Jaff, M., Goldmakher, G., Lev, M., Romero, J. (2008) Imaging of carotid arteries: the role of duplex ultrasonography, magnetic resonance arteriography, and computerised tomographic arteriography. Vascular Medicine, 13, 281-292. Retrieved from http://vmj.sagepub.com/content/13/4/281.full.pdf • Josephson, S A., Bryant, S O., Mak, H K., Johnston, S C., Dillon, W P., Smith, W S.,(2004) Evaluation of carotid stenosis using CT angiography in the initial evaluation of stroke and TIA. Neurology, 63, 3 457-460. doi: 10.1212/WNL.0000135154.53953.2c • Joshi, J. and Prabhakaran, S. (2010) Diagnosis of Intracranial Stenosis. The Open Atherosclerosis and , Thrombosis Journal, 3,Retrieved from http://www.benthamscience.com/open/toathertj/articles/V003/SI0001TOATHERTJ/8TOATHERTJ.pdf • Keogh, B., Bidstrup, B., Taylor, K., Sapsford, R. (1991) Angioscopic evaluation of intravascular morphology after coronary endarterectomy. Ann Thorac Surg, 52: 766-772. Retrieved from http://ats.ctsnetjournals.org/cgi/reprint/52/4/766.pdf • Koelemay, M. J., Nederkoorn, P. J., Reitsma, J. B., & Majoie, C. B. (2004). Systematic review of computed tomographic angiography for assessment of carotid artery disease. [Meta-Analysis Review]. Stroke; a journal of cerebral circulation, 35(10), 2306-2312. doi: 10.1161/01.STR.0000141426.63959.cc • Landwehr, P., Schulte, O., Voshage, G (2001) Ultrasound examination of carotid and vertebral arteries. Eur Radiol; 11:1521–1534 • Magarelli, N et al. (1998) "Carotid stenosis: a comparison between MR and spiral CT angiography." Neuroradiology 40.6: 367-373. • Maldonado, T. (2007) What are Current Procedure Imaging Requirements for Carotid Artery Stenting and Carotid Endarterectomy: Have Magnetic Resonance Angiography and Computed Tomographic Angiography Made a Difference? Seminars in Vascular Surgery, Vol 20, Issue 4, Pages 205-215 http://www.sciencedirect.com.ezproxy2.library.usyd.edu.au/science/article/pii/S0895796707000622 • Muir, K., & Santosh, C. (2005). Imaging of Actue Stroke and Transient Ischaemic Attack. J Neurol Neurosurg Psychiatry, 76(iii), iii19-iiii28. doi: 10.1136/jnnp.2005.075168
  34. 34. References • Patel, S., Collie, D., Wardlaw, J., Lewis, S., Wright, A., Gibson, R., Sellar, R. (2002) Outcome, observer reliability and patient preferences if CTA, MRA, or Doppler ultrasound were used, individually or together, instead of digital subtraction angiography before carotid endarterectomy. Journal of Neurological Neurosurgery Psychiatry, 73:21-28. Retrieved from http://jnnp.bmj.com/content/73/1/21.full • Roh, H., Byun, H., Ryoo, J., Na, D., Moon, W., Lee, B., Kim, D. (2005) American Journal of Neuroradiology, 26: 376-384. Retrieved from http://www.ajnr.org/content/26/2/376.full • Ruggieri, P., Masaryk, T., & Ross, J. (1991). Magnetic Resonance Angiography; Cerebrovascular Applications. Current Concepts of Cerebrovascular Disease and Stroke, 26, 29-36. • Sorensen, G., Ay, H., (2011). Transient Ischemic Attack Definition, Diagnosis and Risk Stratification. Neuroimaging Clin N Am. 21(2): 303-313. Doi: 10.1016/j.nic.2011.01.013 • Silvennoinen, HM., Ikonen, S., Railo, M., Valanne, L. (2007) CT Angiographic Analysis of Carotid Stenosis: Comparison of Manual Assessment, Semiautomatic Vessel Analysis, and Digital Subtraction Angiography. American Journal of Neuroradiology, 28:97-103 Retrieved from http://www.ajnr.org/content/28/1/97.long • Smith, W.S., Roberts, H.C., Chuang, N.A., Ong, K.C., Lee, T.J., Johnston, S.C., Dillon, W.P (2003) Safety and feasibility of a CT protocol for acute stroke: Combined CT, CT Angiography, and CT Perfusion Imaging in 53 Consecutive Patients. American Journal of Neuroradiology 24:688-690 Retrieved from http://www.ajnr.org/content/24/4/688.full.pdf • Solenski, NJ. (2004) Transient Ischemic Attacks: Part I. Diagnosis and Evaluation. American Academy of Family Physicians, Volume 69, 7, pp. 1665-1674. Retrieved from http://www.aafp.org/afp/2004/0401/p1665.html • Streifler, J., Eliasziw, M., Fox, A., Benavente, O., Hachinski, V., Ferguson, G., Barnett, H. (1994) Angiographic detection of carotid plaque ulceration. Comparison with surgical observations in a multicentre study. North Merican Symptomatic Carotid Endarterectomy Trial. Stroke, 25: 1130-1132. Retrieved from http://stroke.ahajournals.org/content/25/6/1130 • Tidy, C. (2011). CT Head Scanning Indications. Retrieved from http://www.patient.co.uk/doctor/CT-Head-Scanning-Indications.htm • Tomanek, A., Coutts, S., Demchuk, A., Hudon, M., Morrish, W., Sevick, R., … Hill, M. (2006). MR Angiography Compared to Conventional Selective Angiography in Acute Stroke. The Canadian Journal of Neurological Sciences, 33, 58-62. • Townsend, T., Saloner, D., Mang Pan, X., & Rapp, J. (2003). Contrast material-enhanced MRA overestimates severity of carotid stenosis, compared with 3D time-of-flight MRA. Journal of Vascular Surgery, 38(1), 36-40. doi:10.1016/S0741-5214(03)00332-X • Upton, J. (2010). Main Stroke Protocol. Retrieved from http://www.nbt.nhs.uk/sites/default/files/filedepot/incoming/Main%20Stroke%20Protocol%20- %20Use%20for%20all%20suspected%20stroke-TIA%20patients.pdf • Wallaert, J., Goodney, P., Vignati, J., Stone, D., Nolan, B., Bertges, D., Walsh, D., Cronenwett, J. (2011) Completion imaging after carotid endarterectomy in Vascular Study Group of New England, J Vsc Surg, 54(2): 376-385. Retriebed from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3237118/ • Wardlaw, J. M., Chappell, F. M., Best, J. J., Wartolowska, K., & Berry, E. (2006). Non-invasive imaging compared with intra-arterial angiography in the diagnosis of symptomatic carotid stenosis: a meta-analysis. [Meta-Analysis Research Support, Non-U.S. Gov't Review]. Lancet, 367(9521), 1503-1512. doi: 10.1016/S0140-6736(06)68650-9
  35. 35. References • Willinek, W., von Falkenhausen, M., Born, M., Gieseke, J., Holler, T., Klockgether, T.,Textor,H., Schild, H., Urbach, H. (2005). Noninvasive Detection of Steno-Occlusive Disease of the Supra-Aortic Arteries With Three-Dimensional Contrast-Enhanced Magnetic Resonance Angiography: A Prospective, Intra-Individual Comparative Analysis With Digital Subtraction Angiography. Stroke, Journal of the American Heart Association, 36, 38-43. doi: 10.1161/01.STR.0000149616.41312.00 • Young, G., Humphrey, P., Shaw, M., Nixon, T., Smith, E. (1999) Comparison of magnetic resonance angiography, duplex ultrasound, and digital subtraction angiography in assessment of extracranial internal carotid artery stenosis. Journal of Neurology, Neurosurgery, and Psychiatry, 57:1466-1478. Retrieved from http://jnnp.bmj.com/content/57/12/1466.short • Yu, D., Schaefer, P., Rordorf, G., & Gonzalez, R. (2002). Magnetic Resonance Angiography in Acute Stroke. Seminars in Roentgenology, 37(3), 212- 218.
  36. 36. Thank you for listening!

×