From the Research
Arteriovenous malformations (AVMs) in the masseter and pterygoid muscles should be treated with embolization as the first line of treatment to reduce blood flow to the AVM and alleviate symptoms, as recommended by the most recent and highest quality study 1.
Symptoms of Masseter and Pterygoid Muscle AVMs
Patients with AVMs in the masseter and pterygoid muscles often experience:
- Facial asymmetry due to swelling in the affected area, which may worsen with physical exertion or Valsalva maneuvers
- Pain, ranging from mild discomfort to severe throbbing pain that can radiate to surrounding areas
- Pulsations in the affected region and sometimes report hearing a buzzing sound (bruit) that corresponds to blood flow through the malformation
- Difficulty with chewing or trismus due to involvement of these masticatory muscles
- Bleeding, which may manifest as oral bleeding if the AVM erodes into the oral cavity
- Paresthesia or numbness in the distribution of the trigeminal nerve branches
Diagnosis and Treatment
Diagnosis typically involves imaging studies such as MRI, CT angiography, or conventional angiography to visualize the vascular malformation.
- Embolization is currently the first line of treatment for these patients, as it can reduce blood flow to the AVM and alleviate symptoms 2.
- Surgical resection or a combination of both approaches may also be considered, depending on the severity of the AVM and the patient's overall health.
- Early evaluation by a multidisciplinary team including interventional radiology and maxillofacial surgery is recommended for optimal management, as these lesions can progressively enlarge and cause increasing symptoms over time 1.
Key Considerations
- The Schobinger clinical classification is important to assess patient evolution and indicate intervention 2.
- Digital subtraction angiography (DSA) is usually performed for guidance during the embolization session and is essential to properly classify a specific lesion, according to its anatomy 2.
- The anatomic classifications proposed by Cho and Yakes are both useful to choose the best therapeutic approach: Endovascular, direct puncture, retrograde venous approach or a combination of these techniques 2.