Current RMA Instruments
| 81 of 2025 | |
| 82 of 2025 |
Changes from previous Instruments
ICD Coding
- ICD-10-AM Codes: I77.3
Brief description
Fibromuscular dysplasia (FMD) is an uncommon condition that affects the walls of medium to small sized arteries. The artery develops areas of narrowing and widening, which can reduce blood flow and lead to ischaemia to the affected organ. The narrowing is non-atherosclerotic (not caused by cholesterol build up) and does not occur as a result of inflammation. FMD most often affects the arteries to the kidneys (renal arteries) and the arteries supplying the brain (carotid arteries). It is a separate condition from a carotid web, which is not covered by this SOP.
Confirming the diagnosis
Diagnosing FMD involves a clinical presentation that suggests reduced blood flow involving a particular artery. This involves a medical practitioner’s assessment of the person’s symptoms and examination findings to be consistent with the diagnosis. To confirm the diagnosis, the following imaging tests will be required to evaluate the structure of the affected arteries and look for characteristic changes- computed tomography angiography (CTA), magnetic resonance angiography (MRA), duplex ultrasonography, or digital subtraction angiography (DSA)– considered the gold standard.
DSA provides the highest-resolution view of the artery but it is an invasive test, so in practice many diagnoses are made using CTA or MRA.
If imaging has not been undertaken, this diagnosis cannot be confirmed. Assessment and management will involve a specialist doctor such as a vascular surgeon, nephrologist, neurologist, or general physician depending on the arteries involved. General practitioners can confirm the diagnosis when supported by consistent clinical findings and appropriate imaging.
Additional diagnoses covered by the SOP
- Nil
Conditions not covered by the SOP
- Atherosclerotic vascular disease
- Carotid web
- Vasculitis
Clinical onset
The clinical onset refers to the earliest point in time, as identified by the treating doctor, when symptoms or signs consistent with fibromuscular dysplasia (FMD) were first observed, prior to the condition being formally diagnosed.
FMD can affect different arteries, and early features depend on which artery is involved. For example, involvement of the kidney 9renal) arteries may result in moderate to severe or difficult-to-control high blood pressure. Involvement of the carotid arteries in the neck may present with headache, pulsatile tinnitus (a whooshing sound in the ear), dizziness, or other symptoms related to reduce blood flow.
Other early indicators may include a cervical or abdominal bruit (an abnormal whooshing sound head with a stethoscope over a narrowed artery), or clinical evidence of ischaemia in the affected organ.
Clinical worsening
When assessing potential clinical worsening, it is important to determine whether any reported deterioration is beyond what would normally be expected from the natural course of FMD.
Management varies depending on the arteries involved and may include medical therapy or procedures to restore blood flow (revascularisation). Despite optimal management, FMD may still progress in some individuals.
The advice by an appropriate medical specialist, such as vascular surgeon, nephrologist, neurologist or general physician is generally required to determine whether true clinical worsening has occurred beyond the expected progression of the disease.