What is the best next step for a 56-year-old hypertensive woman with a non-healing ulcer over her right lateral malleolus, normal pulse, and local exam showing dark discoloration of the skin around the ulcer and a viable ulcer bed?

Venous Duplex Ultrasound is the Best Next Step for a Hypertensive Patient with a Non-healing Lateral Malleolar Ulcer

The best next step for this 56-year-old hypertensive woman with a non-healing ulcer over the right lateral malleolus, normal pulse, and dark discoloration around the ulcer is Venous Duplex Ultrasound (Option B).

Rationale for Venous Duplex Ultrasound

The clinical presentation strongly suggests venous etiology for the following reasons:

1. Location of the ulcer: The lateral malleolus is a classic location for venous ulcers
2. Dark discoloration around the ulcer: Consistent with hemosiderin deposition from venous hypertension
3. Normal pulse: Indicates adequate arterial supply, making primary arterial etiology less likely
4. Viable ulcer bed: Suggests adequate perfusion to maintain tissue viability

According to the IWGDF guidelines, venous disease should be evaluated in patients with non-healing ulcers, especially when the clinical presentation is consistent with venous insufficiency 1. Venous duplex ultrasound provides detailed information about venous reflux, obstruction, and valvular incompetence that are critical for management decisions.

Why Not the Other Options?

Arterial Doppler US (Option C)

While arterial assessment is important, the patient has normal pulses, suggesting adequate arterial supply. The IWGDF guidelines recommend arterial assessment when pulses are absent or when there are signs of arterial insufficiency 1. The clinical presentation (location, appearance, normal pulses) points more toward venous rather than arterial etiology.

CT Angiogram (Option A)

CT angiogram is more invasive, involves radiation exposure and contrast, and would be indicated only if there were signs of significant arterial disease or if non-invasive tests were inconclusive. The IWGDF guidelines suggest starting with non-invasive bedside tests before proceeding to more advanced imaging 1.

Conventional Angiography (Option D)

This is the most invasive option with highest risk and should be reserved for cases where revascularization is planned based on previous non-invasive testing. The IWGDF guidelines state that "Colour Doppler ultrasound, computed tomography angiography, magnetic resonance angiography or intra-arterial digital subtraction angiography can each be used to obtain anatomical information when revascularisation is necessary" 1, indicating that conventional angiography should not be the first diagnostic step.

Diagnostic Algorithm for Non-healing Ulcers

1. Clinical assessment:

   • Location (lateral malleolus suggests venous etiology)
   • Appearance (dark discoloration suggests venous stasis)
   • Pulse examination (normal in this case)

2. Initial non-invasive testing:

   • Venous duplex ultrasound for suspected venous disease
   • Ankle-brachial index (ABI) or arterial Doppler if arterial disease is suspected

3. Advanced imaging only if initial testing is inconclusive or if revascularization is being considered

Key Considerations

• Venous ulcers are the most common type of lower extremity ulcers, accounting for approximately 70% of cases
• The characteristic location over the malleolus and dark discoloration are highly suggestive of venous etiology
• Venous duplex ultrasound can identify reflux, obstruction, and valvular incompetence that guide treatment
• Management will likely include compression therapy, which is the mainstay of treatment for venous ulcers
• Early diagnosis and appropriate management significantly reduce morbidity and improve quality of life

Venous duplex ultrasound represents the optimal balance of diagnostic yield, safety, and resource utilization for this clinical presentation and will provide the most useful information to guide further management.