- Increased serum vascular endothelial growth factor levels and intrathyroidal vascular area in patients with Graves' disease and Hashimoto's thyroiditis. Iitaka, M., Miura, S., Yamanaka, K., Kawasaki, S., Kitahama, S., Kawakami, Y., Kakinuma, S., Oosuga, I., Wada, S., Katayama, S. J. Clin. Endocrinol. Metab. (1998)