- Pathophysiologic observations and histopathologic recognition of the portal hyperperfusion or small-for-size syndrome. Demetris, A.J., Kelly, D.M., Eghtesad, B., Fontes, P., Wallis Marsh, J., Tom, K., Tan, H.P., Shaw-Stiffel, T., Boig, L., Novelli, P., Planinsic, R., Fung, J.J., Marcos, A. Am. J. Surg. Pathol. (2006)