The key difference between AVM and AVF is that AVM is a vascular malformation that occurs within the tissue of the brain or spinal cord, while AVF is a vascular malformation that occurs in the coverings of the brain or spinal cord, such as the dura mater or arachnoid.
A vascular malformation is a condition that causes an abnormal collection or tangle of blood vessels on, in, or near the spinal cord. They are rare medical conditions of the vascular system. The two most common vascular malformations are AVM and AVF.
CONTENTS
1. Overview and Key Difference
2. What is AVM
3. What is AVF
4. Similarities – AVM and AVF
5. AVM vs AVF in Tabular Form
6. Summary – AVM vs AVF
What is AVM?
Arteriovenous malformation (AVM) is a vascular malformation that occurs within the tissue of the brain or spinal cord. This condition happens when oxygen-rich blood that normally enters the spinal cord through arteries and blood vessels bypasses the blood vessels or capillaries. This oxygen-rich blood later directly passes into the veins. AVM can also be caused by abnormal connections between arteries and veins in the brain. Therefore, AVM happens when blood flows quickly and directly from the arteries to the veins bypassing the surrounding tissues in the brain and spinal cord. AVM is triggered by inherited factors (hereditary hemorrhagic telangiectasia (HHT) and Osler-Weber-Rendu syndrome) and problems in fetal development. The signs and symptoms of this condition may include seizures, severe headache or pain in one area of the head, muscle weakness or numbness in a part of the body, vision loss, difficulty speaking, confusion, and severe unsteadiness.
Moreover, AVM can be diagnosed through physical examination, cerebral angiography, CT scan, MRI, and neurological examination. Furthermore, treatment options for AVM may include medications for seizures and headaches, surgical removal (resection), endovascular embolization, stereotactic radiosurgery (SRS), radiosurgery, and micro-surgery techniques.
What is AVF?
AVF is a vascular malformation that occurs in the coverings of the brain or spinal cord, such as the dura mater or arachnoid. AVF is also due to an irregular connection between an artery and a vein. In this condition, blood flows directly from an artery into a vein, avoiding some capillaries. However, AVF occurs in the coverings of the brain or spinal cord rather than within the brain and spinal. AVF is triggered by injuries that pierce the skin, congenital factors, genetic conditions, and dialysis-related surgery. The signs and symptoms of AVF may include purplish, bulging veins seen in the skin, swelling in the arms and legs, reduced blood pressure, fatigue, heart failure, cyanosis, and coughing up blood.
Figure 01: AVF
Moreover, AVF can be diagnosed through physical examination, duplex ultrasound, computerized tomography (CT) angiogram, and magnetic resonance angiography (MRA). Furthermore, treatment options for AVF may include ultrasound-guided compression, catheter embolization, and surgery.
What are the Similarities Between AVM and AVF?
- AVM and AVF are two different types of vascular malformations.
- Both these conditions are due to an irregular connection between an artery and a vein.
- These conditions may cause similar symptoms, such as confusion, weakness, communication problems, etc.
- They can be diagnosed through physical examination and imaging testing.
- They are mainly treated through surgeries.
What is the Difference Between AVM and AVF?
AVM is a vascular malformation happening within the tissue of the brain or spinal cord, while AVF is a vascular malformation happening in the coverings of the brain or spinal cord, such as the dura mater or arachnoid. Thus, this is the key difference between AVM and AVF. Furthermore, AVM is triggered by inherited factors (hereditary hemorrhagic telangiectasia (HHT) and Osler-Weber-Rendu syndrome) and problems in fetal development. On the other hand, AVF is triggered by injuries that pierce the skin, congenital factors, genetic conditions, and dialysis-related surgery.
The below infographic presents the differences between AVM and AVF in tabular form for side-by-side comparison.
Summary – AVM vs AVF
Vascular malformations are rare medical conditions affecting the vascular system, such as veins, arteries, and lymph vessels. AVM and AVF are two different types of vascular malformations. AVM occurs within the tissue of the brain or spinal cord, while AVF occurs in the coverings of the brain or spinal cord, such as the dura mater or arachnoid. So, this summarizes the difference between AVM and AVF.
Reference:
1. “Arteriovenous Fistula (AVF).” Johns Hopkins Medicine.
2. “Brain AVM (Arteriovenous Malformation).” Mayo Clinic.
Image Courtesy:
1. “Schema fistule arterio-veineuse – AV fistula” By Pravdaz – Own work (CC BY-SA 3.0) via Commons Wikimedia