===== Tortuous Vessel =====

**Definition:**  
A tortuous vessel is a **blood vessel that exhibits abnormal twisting, looping, or excessive curvature**, deviating from its expected anatomical path. Tortuosity can affect both arteries and veins and may be congenital or acquired.

**Clinical implications:**  
  * Increases technical difficulty during endovascular procedures.  
  * May contribute to **altered hemodynamics**, **stenosis**, or **flow limitation**.  
  * Commonly seen in elderly patients or those with **hypertension**, **arterial elongation**, or **vascular malformations**.

**Imaging and diagnosis:**  
  * Digital subtraction angiography (DSA)  
  * Computed tomography angiography (CTA)  
  * Magnetic resonance angiography (MRA)  
  * 3D reconstruction in neurovascular planning

**Common locations:**  
  * Internal carotid artery  
  * Vertebral artery  
  * Sigmoid/transverse sinus  
  * Retinal vessels

**Related terms:**  
  * [[trackability]]  
  * [[steerability]]  
  * [[vascular elongation]]  
  * [[stenosis]]