Benavente et al evaluated the risk for stroke in patients with carotid artery stenosis who present with transient monocular blindness. This can help identify those patients who may benefit from surgical endartectomy or be better managed medically. The authors are from University of Texas at San Antonio, University of Western Ontario, and the Rabin Medical Center in Israel.
Patient selection:
(1) stenosis of the internal carotid artery
(2) transient monocular blindness
Parameters:
(1) age
(2) gender
(3) history of stroke
(4) history of intermittent claudication
(5) percent carotid stenosis
(6) collateral circulation
Parameters |
Finding |
Points |
age of the patient in years |
>= 75 years |
0 |
|
< 75 |
1 |
gender of the patient |
female |
0 |
|
male |
1 |
history of hemispheric transient ischemic attack (TIA) or stroke |
absent |
0 |
|
present |
1 |
history of intermittent claudication |
absent |
0 |
|
present |
1 |
percent carotid artery stenosis |
< 80% (50 - 79%) |
0 |
|
80 - 94% |
1 |
|
near occlusion |
0 |
collateral circulation |
present |
0 |
|
absent |
1 |
where:
• The failure of near occlusion being a risk factor strikes me as odd. I wonder how often patients with severe occlusion rarely present with transient monocular blindness.
number of risk factors =
= SUM(points for all 6 parameters)
Interpretation:
• minimum number of risk factors: 0
• maximum number of risk factors: 6
• The greater the number of risk factors, the greater the risk of stroke in the patient.
Number of Risk Factors |
Risk Group |
Risk of Stroke in 3 Years with Medical Management |
0 or 1 |
low |
1.8% |
2 |
moderate |
12.3% |
3 to 6 |
high |
24.2% |
Risk Group |
Absolute Risk Reduction with Endartectomy |
low |
increases risk 2.2 |
moderate |
decreases risk 4.9 |
high |
decreases risk 14.3 |
Specialty: Neurology
ICD-10: ,