Dizziness and fainting but don't know why (Medical Mystery)

1. Type of Trauma: None

2. Sign and Symptoms: Dizziness, Headache, Neck Pain, Syncope (Fainting)

3. Imaging findings: Agenesis of the C1 Posterior arch.

4. Adjustments: None

5. Outcome: Patient was referred for further investigation.

   
   

Mid 40s male visited Headache and Neck Clinic for his dizziness, neck pain, and drop attacks (cardiovascular syncope). The patient was already nearly fainting by just doing a normal cervical rotation by reaching the end range of motion. There is a condition called Bow Hunter Syndrome. When the hunter uses the bow to shoot the arrow, they turn their head. There are occasions where the hunters find themselves on the ground and realize they passed out. Bow Hunter's Syndrome (BHS), also known as rotational vertebral artery (VA) syndrome, refers to symptomatic vertebrobasilar insufficiency (VBI) caused by mechanical occlusion or compression of the VA at the atlantoaxial or subaxial level during neck and head rotation.

During the physical examination, the patient's dizziness certainly was reproduced with cervical rotation, and continuing in the rotated position gave him the sensation of passing out.

CBCT revealed an agenesis of the posterior arch of C1, resulting in a forward transition of the C1 TVP which could choke the internal jugular veins between the elongated styloid processes, and the forward transition of the C1 TVP will displace the transverse foramen forwardly as well, thus affecting the vertebral arteries and veins as well.

1. Agenesis of the C1 posterior arch

2. Vertebrobasilar insufficiency syndrome (Bow-hunter syndrome) due to the possible bilaterally disrupted internal jugular veins and vertebral arteries and veins

The patient was absolutely unaware of these underlying issues, despite being hospitalized for a month in the past to investigate the cause of his slow heart rate (bradycardia) and resulting syncope. Further assessments, such as an MRI to ensure the sound integrity and function of the spinal cord and the structures at the craniocervical junction (CCJ), were recommended. As a result, he was referred to his GP for additional evaluation.