Absent anterior communicating artery and varied distribution on anterior cerebral artery

During the cerebral dissection of a 67-year-old male cadaver, a unique combination of variations at the circle of Willis and anterior cerebral artery [ACA] distribution were encountered. The A1 segment of both ACA were fused without an anterior communicating artery [ACoA], forming an X shape and giving rise to a common pericallosal artery [CPA], an incomplete distal ACA, and an incomplete distal anterior cerebral artery [IACA]. The IACA had an unusual course, which may be important from the surgical point of view. The CPA continued as the A2 and A3 segments, and bifurcated into 2 pericallosal arteries. Branching patterns of the varied arteries to the interhemispheric region were evaluated, and results were discussed. Additionally, both posterior communicating arteries were hypoplastic. There was no aneurysm formation at the circle of Willis and its branches

case of large scalenus minimus muscle

During the dissection of an 80-year-old, white, male cadaver, a large scalenus minimus muscle was detected on the right side. Scalenus minimus muscle, a fiber bundle which strengthens the suprapleural membrane, arises from the anterior tubercle of the transverse process of the 7th cervical vertebra, and inserts to the inner border of the first rib and cupula pleura. In the present case, the scalenus minimus muscle on the suprapleural membrane was large on the right side. Its origin was on the anterior tubercle of the transverse process of the 7th cervical vertebra, and the muscle was located between the C7 and C8 anterior rami. The present case is noteworthy because of its great dimension and relation with the brachial plexus. Apart from its importance in cervical region anesthesia and surgery such an anatomical structure can lead to several clinical conditions both by spasm and compression such as neurogenic thoracic outlet syndrome