Hematology focuses on diseases of the blood, bone marrow, and lymphatic system. Learn about the diagnosis and treatment of anemia, leukemia, and lymphoma.
Send us all your questions or requests, and our expert team will assist you.
The diagnosis of Deep Vein Thrombosis is a structured process that moves from clinical suspicion to laboratory screening and finally to confirmatory imaging. Because the stakes are high—a missed diagnosis can lead to fatal pulmonary embolism, while a false positive exposes a patient to the risks of unnecessary anticoagulation—accuracy is paramount. Liv Hospital employs a comprehensive diagnostic protocol using state-of-the-art technology to evaluate the anatomy of the veins and the dynamics of blood flow.
Before ordering scans, clinicians evaluate the likelihood of DVT using validated scoring systems. This prevents over-testing and guides the interpretation of results.
The Wells Score
The Wells criteria assign points for active cancer, paralysis, bedridden status, localized tenderness, leg swelling, calf swelling, pitting edema, collateral superficial veins, and previous DVT history.
Risk Stratification
Patients are categorized as “likely” or “unlikely” to have DVT. This stratification dictates the next step in the diagnostic algorithm, ensuring a logical and efficient path to diagnosis.
The D-dimer test is a crucial exclusion tool in the diagnostic pathway.
Biological Basis
When a blood clot forms, the body eventually starts to break it down. D-dimer is a protein fragment produced when a blood clot dissolves. It is essentially a degradation product of cross-linked fibrin.
Interpreting Results
A normal (negative) D-dimer level effectively rules out acute DVT in patients with a low clinical probability. However, an elevated (positive) D-dimer is non-specific; it can be raised by recent surgery, pregnancy, trauma, infection, or cancer. Therefore, a positive test necessitates imaging to confirm the presence of a clot.
Venous ultrasonography is the standard imaging modality for diagnosing DVT. It is non-invasive, radiation-free, and highly accurate for proximal clots.
Compression Ultrasound
The sonographer applies pressure with the transducer probe over the veins. A healthy vein has thin walls and collapses completely under pressure. If a vein does not collapse, it indicates that a solid thrombus is preventing the walls from meeting.
Doppler Evaluation
Doppler technology uses sound waves to evaluate the speed and direction of blood flow. It can detect if blood flow is absent, turbulent, or lacking the normal respiratory variations that occur with breathing.
Color Flow Imaging
This feature superimposes color on the image to visualize blood movement. A lack of color filling in the vessel lumen suggests a blockage.
When ultrasound is inconclusive or when the clot is suspected to be in the pelvic or abdominal veins (where ultrasound visibility is poor due to bowel gas or bone), advanced imaging is required.
CT Venography (CTV)
Computed Tomography Venography involves injecting contrast dye into a vein and taking rapid X-ray slices. It provides a detailed 3D map of the venous system and is often performed alongside a CT Pulmonary Angiogram (CTPA) to check for concurrent pulmonary embolism.
Magnetic Resonance Venography (MRV)
MRV uses magnetic fields to visualize veins. It is particularly useful for pregnant women (to avoid radiation) and patients with renal failure who cannot tolerate CT contrast agents. It is highly sensitive for detecting pelvic vein thrombosis.
Contrast venography involves injecting dye directly into a vein in the foot and taking X-rays as the dye travels up the leg.
Current Indications
While largely replaced by ultrasound, it remains useful in rare, complex cases or during interventional procedures where a catheter is already being used to treat the clot. It provides the most definitive image of the clot’s architecture.
If DVT is confirmed, clinicians must assess for PE, even if respiratory symptoms are mild.
CT Pulmonary Angiogram
This is the primary test for PE. It visualizes the pulmonary arteries to see if any clot fragments have lodged in the lungs.
V/Q Scan
A Ventilation Perfusion scan is an alternative for patients who cannot have a CT scan. It compares air flow and blood flow in the lungs to identify mismatches indicative of a clot.
If a patient develops DVT without a clear trigger (like surgery or travel), it is classified as “unprovoked.” This prompts a deeper investigation into underlying causes.
Thrombophilia Screening
This involves blood tests for genetic clotting disorders (Factor V Leiden, Prothrombin mutation) and deficiencies in natural anticoagulants (Antithrombin, Protein C, and S). These tests are usually done weeks after the acute event and after stopping blood thinners to ensure accuracy.
Cancer Screening
Since unprovoked DVT can be the first sign of an occult malignancy, age-appropriate cancer screening (mammogram, colonoscopy, PSA) is reviewed and updated.
Part of the evaluation involves ruling out other conditions that look like DVT.
Baker’s Cyst Rupture
A fluid-filled cyst behind the knee can burst, causing fluid to leak into the calf muscle. This produces sudden pain and swelling that mimics DVT perfectly. Ultrasound can easily distinguish a fluid collection from a clot.
Cellulitis
This bacterial skin infection causes redness, warmth, and swelling. Unlike DVT, cellulitis usually affects the skin surface and is associated with fever and distinct borders of redness.
Muscle Strain
A tear in the gastrocnemius muscle (tennis leg) causes sudden calf pain and swelling. The history usually involves a sudden injury during activity, unlike the more gradual onset of DVT pain.
Send us all your questions or requests, and our expert team will assist you.
While clinical signs and blood tests give strong clues, they are not definitive. Ultrasound or other imaging is almost always required to confirm the diagnosis and determine the extent of the clot.
The D-dimer test is excellent at ruling out DVT (high sensitivity) but poor at confirming it (low specificity). A negative result is very reliable, but a positive result needs further investigation.
Standing increases the pressure in the leg veins, expanding them and making it easier for the sonographer to identify clots and check for valve damage (reflux).
Ultrasound and MRI do not use ionizing radiation. CT scans and contrast venography do use radiation, which is why they are used selectively, especially in young patients or during pregnancy.
The D-dimer test is excellent at ruling out DVT (high sensitivity) but poor at confirming it (low specificity). A negative result is very reliable, but a positive result needs further investigation.
Buerger’s disease, also known as thromboangiitis obliterans, is a rare condition. It’s mainly caused by tobacco use. It harms the small and medium-sized arteries and
Recognizing the signs of a blood clot on top of the foot is crucial for prompt treatment. Symptoms include sudden swelling, pain, warmth, redness, or
Did you know nearly 900,000 people in the United States get blood clots each year? Many face serious health risks. Your sleeping position can affect
Nearly 900,000 Americans face blood clots each year. Many cases are life-threatening if not caught early. A blood clot in the leg can cause serious
Pregnancy brings many changes to the body. While these changes are needed for a healthy pregnancy, they also raise the risk of problems like blood
Nearly 900,000 Americans are affected by blood clots each year. Many experience symptoms that can be confused with other conditions. It’s important to know how
Leave your phone number and our medical team will call you back to discuss your healthcare needs and answer all your questions.
Your Comparison List (you must select at least 2 packages)
