I66.22: Occlusion and stenosis of left posterior cerebral artery

I66.22, occlusion and stenosis of left posterior cerebral artery, is listed as a covered diagnosis in 16 Medicare billing and coding articles that apply to 60 HCPCS Level II codes, including C8925 (Transesophageal echocardiography (tee) with contrast, or…), C8926 (Transesophageal echocardiography (tee) with contrast, or…), C8927 (Transesophageal echocardiography (tee) with contrast, or…). The articles come from 6 Medicare contractors. A listed diagnosis supports medical necessity only; coverage still depends on the LCD's criteria and on documentation in the medical record.

HCPCS Level II codes with I66.22 as a covered diagnosis

CodeDescriptionMedicare coverageDMEPOS fee 2026 (state range)Articles listing it
C8925Transesophageal echocardiography (tee) with contrast, or without contrast followed by with contrast, real time with image documentation (2d) (with or without m-mode recording); including probe placement, image acquisition, interpretation and reportSpecial coverage instructions apply—4
C8926Transesophageal echocardiography (tee) with contrast, or without contrast followed by with contrast, for congenital cardiac anomalies; including probe placement, image acquisition, interpretation and reportSpecial coverage instructions apply—4
C8927Transesophageal echocardiography (tee) with contrast, or without contrast followed by with contrast, for monitoring purposes, including probe placement, real time 2-dimensional image acquisition and interpretation leading to ongoing (continuous) assessment of (dynamically changing) cardiac pumping function and to therapeutic measures on an immediate time basisSpecial coverage instructions apply—4
J0461Injection, atropine sulfate, 0.01 mgSpecial coverage instructions apply—4
J0153Injection, adenosine, 1 mg (not to be used to report any adenosine phosphate compounds)Special coverage instructions apply—4
J1250Injection, dobutamine hydrochloride, per 250 mgSpecial coverage instructions apply—4
J0280Injection, aminophyllin, up to 250 mgSpecial coverage instructions apply—4
J1245Injection, dipyridamole, per 10 mgSpecial coverage instructions apply—4
Q9957Injection, perflutren lipid microspheres, per mlCarrier judgment—3
Q9956Injection, octafluoropropane microspheres, per mlCarrier judgment—3
Q9955Injection, perflexane lipid microspheres, per mlCarrier judgment—3
C8900Magnetic resonance angiography with contrast, abdomenSpecial coverage instructions apply—3
C8901Magnetic resonance angiography without contrast, abdomenSpecial coverage instructions apply—3
C8902Magnetic resonance angiography without contrast followed by with contrast, abdomenSpecial coverage instructions apply—3
C8909Magnetic resonance angiography with contrast, chest (excluding myocardium)Special coverage instructions apply—3
C8910Magnetic resonance angiography without contrast, chest (excluding myocardium)Special coverage instructions apply—3
C8911Magnetic resonance angiography without contrast followed by with contrast, chest (excluding myocardium)Special coverage instructions apply—3
C8912Magnetic resonance angiography with contrast, lower extremitySpecial coverage instructions apply—3
C8913Magnetic resonance angiography without contrast, lower extremitySpecial coverage instructions apply—3
C8914Magnetic resonance angiography without contrast followed by with contrast, lower extremitySpecial coverage instructions apply—3
C8918Magnetic resonance angiography with contrast, pelvisSpecial coverage instructions apply—3
C8919Magnetic resonance angiography without contrast, pelvisSpecial coverage instructions apply—3
C8920Magnetic resonance angiography without contrast followed by with contrast, pelvisSpecial coverage instructions apply—3
A9700Supply of injectable contrast material for use in echocardiography, per studySpecial coverage instructions apply—3
G0453Continuous intraoperative neurophysiology monitoring, from outside the operating room (remote or nearby), per patient, (attention directed exclusively to one patient) each 15 minutes (list in addition to primary procedure)Carrier judgment—2

35 more codes are listed. See every code with payment by region in Caduvo.

Medicare policy articles listing I66.22

1 more articles list I66.22.

A diagnosis listed as covered in a billing and coding article supports medical necessity for the article's codes; it does not guarantee payment. Coverage depends on the LCD's criteria, the contractor's jurisdiction and documentation in the medical record.

Other I66 diagnoses (Occlusion and stenosis of cerebral arteries, not resulting in cerebral infarction)

Frequently asked questions

Does Medicare cover I66.22 (Occlusion and stenosis of left posterior cerebral artery)?

Medicare covers items and services, not diagnoses. 16 Medicare billing and coding articles list I66.22 as a covered diagnosis for 60 HCPCS Level II codes: the diagnosis can support medical necessity for those codes, but payment still depends on the LCD's coverage criteria and the medical record.

Which HCPCS codes can be billed with ICD-10 I66.22?

The Level II codes from the policies most specific to this diagnosis are C8925 (Transesophageal echocardiography (tee) with contrast, or…, 4 articles); C8926 (Transesophageal echocardiography (tee) with contrast, or…, 4 articles); C8927 (Transesophageal echocardiography (tee) with contrast, or…, 4 articles); J0461 (Injection, atropine sulfate, 0.01 mg, 4 articles); J0153 (Injection, adenosine, 1 mg (not to be used to report any…, 4 articles). Code choice depends on the item supplied; check each code's descriptor.

Which Medicare policy articles list I66.22?

A57179 (Billing and Coding: Transesophageal Echocardiogram); A56809 (Billing and Coding: Transesophageal Echocardiography (TEE)); A56505 (Billing and Coding: Transesophageal Echocardiography (TEE)), and 13 more articles.

What is ICD-10-CM code I66.22?

I66.22 is the ICD-10-CM code for occlusion and stenosis of left posterior cerebral artery, in category I66 (Occlusion and stenosis of cerebral arteries, not resulting in cerebral infarction), chapter 9: Diseases of the circulatory system.

Next steps

Sources: CMS Medicare Coverage Database billing and coding articles (covered ICD-10 code lists and HCPCS links); ICD-10-CM FY2026; CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule 2026 (non-rural state fees). Not billing or legal advice.

Chapter 9: Diseases of the circulatory system · All diagnoses · HCPCS lookup