The idea that assessment is intrinsic to effective instruction is traced from early experiments in the individualization of learning through the work of Benjamin Bloom to reviews of the impact of feedback on learners in classrooms.
Incidental hypervascular lesions are also very common findings in liver imaging. It is important to differentiate between 'touch' and 'don't touch' lesions. Benign 'don't touch' hypervascular tumors include hemangioma, FNH and small adenomas.
Painless loss of monocular vision is the usual presenting symptom of retinal artery occlusion (RAO). Ocular stroke commonly is caused by embolism of the retinal artery, although emboli may travel to distal branches of the retinal artery, causing loss of only a section of the visual field.