[The accessory middle cerebral artery (author's transl)]

Area of Science:

• Neuroanatomy
• Vascular Neurology
• Radiology

Background:

• The accessory middle cerebral artery (AMCA) is a rare anatomical variation.
• Documented cases of AMCA are infrequent in medical literature.

Observation:

• Four cases of AMCA were identified in 1240 carotid angiograms, yielding an incidence of 0.24% to 0.34%.
• Patients' ages ranged from 45 to 56 years, with equal male and female distribution.
• Angiography was performed due to neurological signs post-head injury or cerebrovascular stroke.
• AMCA was an incidental finding in all cases.
• The anomalous arteries originated from the anterior cerebral artery and coursed parallel to the middle cerebral artery stem.
• Two AMCAs supplied perforating arteries to the brain.
• AMCA was easily visualized on antero-posterior angiographic projections.

Findings:

• Selective middle cerebral artery angiography in one patient aided in identifying the AMCA.
• The AMCA was observed running in an elliptic circle above D1 on lateral projections.
• No association was found between AMCA and intracranial aneurysms or other anomalies like agenesis of the corpus callosum or reduplication of the Circle of Willis.

Implications:

• This study contributes to the understanding of rare cerebral vascular variations.
• Accurate identification of AMCA on routine carotid angiograms is crucial for accurate neurovascular assessment.
• Further research may elucidate the clinical significance, if any, of this anatomical variant.