Protective Felix Culpa Effect of Superior Sympathetic Cervical Ganglion Degenerations on Prevention of Basilar Artery Spasm After Subarachnoid Hemorrhage: A Preliminary Experimental Study

World Neurosurg. 2022 Aug:164:e861-e867. doi: 10.1016/j.wneu.2022.05.063. Epub 2022 May 20.

Abstract

Background: Posterior cerebral blood flow is regulated by the basilar arteries (BAs). Vasospasm of BAs can occur after subarachnoid hemorrhage (SAH). Superior cervical sympathetic ganglia (SCG) fibers have a vasoconstrictor effect on the BA. We aimed to investigate the relationship between the degenerated neuron density of the SCG and the severity of BA vasospasm after experimental SAH.

Methods: Twenty-four rabbits were used. Five were used as the control group, and 5 were used as the sham group. Experimental SAHs were performed in the remaining 14 animals (study group) by injecting homologous blood into the cisterna magna. After 3 weeks of injection, neuron densities of SCG and the severity of BA vasospasm index values (VSI) were examined histopathologically and compared statistically.

Results: The mean VSI was 0.669 ± 0.1129 in the control group, 0.981 ± 0.159 in the sham group, and 1.512 ± 0.298 in the study group. The mean degenerated neuronal density of SCG was 436 ± 79/mm3 in severe vasospasm (n = 3), 841 ± 101/mm3 in moderate vasospasm (n = 4), and 1.921 ± 849/mm3 in the less vasospasm detected animals (n = 6).

Conclusions: This study shows an inverse relationship between the degenerated neuronal density in the SCG and VSI values. This finding indicates a diminished sympathetic input from the SCG, resulting in a beneficial effect (the felix culpa) by dilating the lumen diameter of the BA, so SCG degeneration after SAH protects the BA spasm.

Keywords: Basilar arteries; Degeneration; Subarachnoid hemorrhage; Superior cervical ganglion; Vasospasm.

MeSH terms

  • Animals
  • Basilar Artery
  • Cisterna Magna
  • Disease Models, Animal
  • Rabbits
  • Spasm
  • Subarachnoid Hemorrhage* / complications
  • Superior Cervical Ganglion
  • Vasospasm, Intracranial* / etiology
  • Vasospasm, Intracranial* / prevention & control