Patient presents with signs and symptoms suggestive of left carotid artery stenosis.  These include transient ischemic attack TIA, amaurosis fugax, focal neurological deficit, or asymptomatic bruit.  The patient's past medical history is significant for risk factors such as hypertension, hyperlipidemia, diabetes mellitus, smoking, and family history of cerebrovascular disease.  Physical examination reveals a carotid bruit audible over the left carotid artery.  Duplex ultrasound of the carotid arteries was performed, revealing a significant stenosis of the left internal carotid artery.  The degree of stenosis was quantified as [percentage] based on peak systolic velocity and end diastolic velocity measurements.  Differential diagnosis includes other causes of cerebrovascular symptoms such as vertebral artery stenosis, cardiac embolism, and intracranial atherosclerosis.  The diagnosis of left carotid stenosis is confirmed by carotid ultrasound findings.  Treatment options including medical management with antiplatelet therapy such as aspirin or clopidogrel, lifestyle modifications such as smoking cessation and dietary changes, and surgical intervention such as carotid endarterectomy or carotid artery stenting were discussed with the patient.  The risks and benefits of each treatment option were explained, and the patient's preferences were considered.  A plan was developed for ongoing monitoring and follow-up care.  ICD-10 code I65.2, Left carotid artery stenosis, and CPT codes for the carotid ultrasound 93880 or 93926 are applicable depending on the specific study performed.  Further evaluation with magnetic resonance angiography MRA or computed tomography angiography CTA may be considered to better characterize the lesion and guide treatment decisions.