A study on the relationship between intraglandular arterial distribution and thyroid lobe shape: Implications for biotechnology of a bioartificial thyroid

We have recently hypothesized that structural and secretory components of theadult human thyroid gland maintain constant reciprocal and geometrical relationships,even if changes occur in the three-dimensional (3D) architecture of any ofthese elements. This means that thyroid morphology could be studied from the pointof view of a 3D topology. As a consequence, we have investigated anatomical aspectsthat could support this assumption. In the present study, we show that the presenceof a constant relationship can be demonstrated between the vascular arrangementof the gland, including the extension of intraglandular arterial fields, arterialanastomoses and arterial calibers, and the shape as well as volume of the thyroid.Specifically, a statistically significant difference has been found between thenetwork amplitudes of the superior and inferior thyroid arteries in relation to eithera conic or an ellipsoidal geometry of the thyroid lobe. In addition, a direct relationship has been implicated between the distribution of arterial anastomosesand the behavior of the lobe as a single hemodynamic unit. Finally, a statisticallysignificant correlation has been observed between average arterial caliber of theinferior thyroid artery and thyroid volume. On the basis of these results, we proposea model of architectural assembly between stromal and parenchymal elements ofthe adult thyroid that might prove useful in designing a bioartificial gland ex situ.Potential clinical applications of this principle in regenerative medicine of otherendocrine organs are highlighted.