Anat Cell Biol.  2024 Dec;57(4):608-611. 10.5115/acb.24.026.

A unilateral partial duplication of a fetal variant posterior cerebral artery associated with anomalous origin of duplicated superior cerebellar artery: a case report

• Elzawawy EM
• Al-Mutori MH
• Awaisi HSA
• Al Dagher AA
• Allayeth MM
• Elsayed HRH

• KMID: 2562509
• DOI: http://doi.org/10.5115/acb.24.026

Abstract

Variations at the junction of embryonic internal carotid and vertebrobasilar systems are rare and associated with a high incidence of stroke. During cadaver dissection, we demonstrated for the first time a case of hypoplastic right vertebral artery associated with partial duplication of the distal part of the right P1 segment of a partial fetal posterior cerebral artery (FPCA) and bilateral duplication of superior cerebellar arteries (SCAs), of which, the upper right SCA originated from PCA. We hypothesize that the poor development of the right half of the vertebrobasilar system caused the persistence of FPCA with anomalous origin of the right upper SCA as well as partial duplication of P1 segment of PCA as a remnant of the weak anastomosis between the embryonic right PCA and the basilar system. Such complex variations provide a huge challenge in their diagnosis and in choosing the suitable treatment modality for the stroke.

Keyword

Posterior communicating artery; Hypoplastic; Posterior cerebral artery; Superior cerebellar artery; Variation

Figure

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  Fig. 1 Diagrammatic Illustration for the development of posterior cerebral artery (PCA). (A) Fetal PCA (FPCA) arises from internal carotid. (B) FPCA makes weak anastomotic network with basilar artery (BA) terminals (Future P1 segment of PCA). (C) The anastomotic network progresses into a larger anastomotic vessel. (D) The proximal part of the FPCA starts to regress to become posterior communicating artery (PComA). 1. Vertebral arteries, 2. BA, 3. BA terminals (future P1 segment of PCA), 4. superior cerebellar arteries, 5. internal carotid artery (ICA), 6. FPCA, 7. anastomosis of ICA with BA terminals, 8. P2 segment of PCA, 9. PComA.

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  Fig. 2 (A) Dissection of the base of the brain and circle of Willis. (B) Illustrative drawing for the brain vessels of the present case. 1. Right internal carotid artery (ICA), 2. left ICA, 3. right posterior communicating artery (PComA) (fetal variant posterior cerebral artery [PCA]), 4. left PComA, 5. right vertebral artery, 6. left vertebral artery, 7. basilar artery, 8. P1a (proximal part of P1 segment) of right PCA, 9. anterior limb of the duplicated P1b (distal part of P1 segment) of right PCA, 10. posterior limb of the duplicated P1b (distal part of P1 segment) of right PCA, 11. P1 segment of left PCA, 12. P2 segment of right PCA (fetal variant), 13. P2 segment of left PCA, 14. upper right superior cerebellar artery (SCA), 15. lower right SCA, 16. upper left SCA, 17. lower left SCA.

Reference

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