Which criteria would be considered diagnostic by NASCET of stenosis with [tex]$\geq 70$[/tex] percent diameter reduction?
A. PSV [tex]$\ \textgreater \ 125 cm / s$[/tex] and EDV [tex]$\ \textless \ 100 cm / s$[/tex]
B. [tex]$PSV \ \textgreater \ 125 cm / sec$[/tex]
C. ICA-to-CCA ratio [tex]$\ \textgreater \ 2: 1$[/tex]
D. ICA-to-CCA ratio [tex]$\geq 4: 1$[/tex]
Answer (1)
The NASCET criteria for diagnosing stenosis with ≥ 70% diameter reduction is an ICA-to-CCA ratio ≥ 4 : 1 . Therefore, the answer is d .
Explanation
Understanding the NASCET Criteria We need to identify the correct NASCET (North American Symptomatic Carotid Endarterectomy Trial) criteria for diagnosing stenosis with a diameter reduction of 70% or greater. The NASCET criteria are based on peak systolic velocity (PSV) and the ratio of the internal carotid artery (ICA) PSV to the common carotid artery (CCA) PSV.
Identifying the Correct Ratio According to NASCET, a ratio of ICA-to-CCA ≥ 4 : 1 is considered diagnostic of stenosis with ≥ 70% diameter reduction.
Conclusion Therefore, the correct answer is d. ICA-to-CCA ratio ≥ 4 : 1 .
Examples
In medical diagnostics, understanding criteria like NASCET is crucial for assessing the severity of conditions such as carotid artery stenosis. For instance, if a patient's ultrasound shows an ICA-to-CCA ratio of 4.5:1, it indicates a significant narrowing of the carotid artery, potentially leading to stroke. This assessment guides doctors in making informed decisions about treatment options, such as surgery or medication, to prevent serious complications. Accurate interpretation of these ratios ensures timely and effective intervention, highlighting the importance of these diagnostic criteria in clinical practice.
