Transcranial Doppler Evaluation
Medicare Approved Indications

• Detection and evaluation of the hemodynamic effects of severe stenosis or occlusion of the extracranial arteries(greater than or equal to 60% diameter reduction) and major basal intracranial arteries (greater than or equal to 50% diameter reduction).
• Evaluation of intracranial hemodynamic abnormalities in patients with suspected brain death.
• Evaluation of cerebral embolization.
• Assessing patterns and extent of collateral circulation in patient with known region of severe stenosis or occlusion.
• Detection and serial evaluation of cerebral vasospasm complicating subarachnoid hemorrhage.
• Evaluation of invasive therapeutic interventions for cerebral malformations.
• Detecting arteriovenous malformation and studying their supply arteries and flow pattern.

Venous Evaluation
Indications / Applications

• Suspected deep venous thrombosis (DVT) of lower or upper extremities
• Unexplained leg swelling after major surgery
• Question of valvular function
• Chronic leg swelling of uncertain cause
• Suspected or proven pulmonary embolus
• Follow-up evaluation of anticoagulant therapy to document status of DVT and valve function
• Vein mapping – upper and lower extremities
• Dialysis graft evaluation

Arterial Evaluation
Indications / Applications

• Absent peripheral pulses
• Leg pain of questionable etiology, intermittent claudication
• Rest pain (diabetic neuropathy or ischemia?)
• Prediction of healing potential for foot ulcers, determination of amputation level
• Question of aneurysm / pseudoaneurysm
• Follow-up to vascular surgery and of medically managed vascular disease
• Arterial trauma
• Digital cyanosis / Raynauds
• Thoracic outlet / compression syndromes

Abdominal Vascular Evaluation
Indications / Applications

• Renal arteries / veins
      Screening for renal vascular hypertension
      Screening for ischemic nephropathy
      Monitoring of known renal artery stenosis or renal bypass graft
• Mesenteric vessels
      Suspected visceral ischemia
      Aneurysm / pseudoaneurysm
• Portal system
      Suspected portal hypertension, portal vein thrombosis
      Shunt evaluation
      Preoperative vessel patency
• Aorta / Iliac system
      Aneurysm evaluation
      Stenosis evaluation
      Graft follow-up
• Inferior vena cava / Iliac venous system
      Suspected thrombosis
      Suspected extrinsic compression