From the Guidelines
For a 78-year-old male with a shiny swollen foot and lower leg, after duplex ultrasound, the next imaging steps should include a CT venogram or MR venogram to evaluate for deep vein thrombosis that may have been missed on ultrasound, as recommended by the most recent guidelines 1. The patient's symptoms could be indicative of various conditions, including deep vein thrombosis, infection, or arterial insufficiency.
- A CT venogram or MR venogram would help evaluate the deep venous system and identify any potential thrombi that may have been missed on ultrasound, which is crucial for preventing further complications such as pulmonary embolism.
- If infection is suspected, an MRI with contrast would be appropriate to assess for osteomyelitis, soft tissue abscess, or cellulitis, as it provides superior soft tissue detail 1.
- A plain radiograph (X-ray) should be obtained to rule out fractures, arthritis, or osteomyelitis, which could also present with similar symptoms.
- Laboratory tests including D-dimer, complete blood count, and inflammatory markers should accompany these imaging studies to help differentiate between various causes of lower extremity edema. The choice between CT and MRI depends on the patient's renal function, as contrast agents used in CT can be nephrotoxic in elderly patients with compromised kidney function, as noted in the American Society of Hematology 2018 guidelines for management of venous thromboembolism 1.
- MRI provides superior soft tissue detail but takes longer and may not be tolerated by patients with claustrophobia or implanted metal devices.
- CT angiography or MR angiography would help evaluate vascular status if arterial insufficiency is a concern, as recommended by the ACR Appropriateness Criteria for sudden onset of cold, painful leg 1. These advanced imaging techniques help differentiate between various causes of lower extremity edema, including venous insufficiency, lymphedema, infection, or cardiac/renal conditions that may present similarly in elderly patients.
From the Research
Next Imaging Steps for Shiny Swollen Foot and Lower Leg
For a 78-year-old male with a shiny swollen foot and lower leg, beyond duplex ultrasound, the following imaging steps can be considered:
- Computed Tomography (CT): CT can be used to rule out other conditions that may be causing the symptoms, such as May-Thurner syndrome or arteriovenous fistula 2.
- Magnetic Resonance Imaging (MRI): MRI can provide detailed images of the soft tissues and blood vessels, helping to diagnose conditions such as deep vein thrombosis (DVT) or compartment syndrome 3.
- Venography: Venography can be used to visualize the veins and diagnose conditions such as DVT or venous insufficiency.
Considerations for Imaging
When selecting an imaging modality, the following factors should be considered:
- Clinical presentation: The patient's symptoms and medical history should guide the choice of imaging modality.
- Risk factors: The presence of risk factors such as trauma, cancer, or hypercoagulability should be taken into account when selecting an imaging modality.
- Availability and accessibility: The availability and accessibility of imaging modalities should be considered, particularly in emergency situations.
Potential Diagnoses
The shiny swollen foot and lower leg could be indicative of several potential diagnoses, including:
- Deep vein thrombosis (DVT): DVT is a blood clot that forms in the deep veins of the leg, which can cause swelling, pain, and discoloration 4, 5, 3, 6.
- Compartment syndrome: Compartment syndrome is a condition where increased pressure within a muscle compartment can cause pain, swelling, and nerve damage 3.
- Venous insufficiency: Venous insufficiency is a condition where the veins have difficulty returning blood to the heart, which can cause swelling, pain, and skin changes.