Related by context. Frequent words. (Click for all words.) 67 retina 62 blood vessels 62 spinal cord 61 cornea 61 macula 60 cerebellum 59 esophagus 59 nerve fibers 58 retinal 58 brain 58 retinas 56 nerve cells 56 internal organs 56 small intestine 55 pituitary gland 54 frontal lobe 54 nerve endings 54 eardrum 53 peripheral vision 53 urethra 53 cortex 52 spinal column 52 pancreas 52 glaucoma 52 coronary artery 51 retinopathy 51 aorta 51 capillaries 51 ventricle 51 diabetic retinopathy 51 liver 51 neurological 50 intestines 50 cataracts 50 corneal 50 breast tissue 50 hair follicles 49 lesion 49 thyroid gland 49 axons 49 trachea 49 intestine 49 digestive tract 49 gastrointestinal tract 49 neuron 49 bladder 49 ear canal 49 neurons 49 inner ear 49 ventricles 48 kidneys 48 uterus 48 soft tissues 48 cerebrospinal fluid 48 arteries 48 cortical 48 myelin 48 gland 48 ovary 47 left ventricle 47 cysts 47 muscle tissue 47 ovaries 47 motor neurons 47 sinuses 47 macular degeneration 47 eyesight 47 adrenal glands 47 cerebral cortex 46 electrical impulses 46 coronary arteries 46 diaphragm 46 neuronal 46 inflammation 46 lungs 46 cyst 46 vital organs 46 neural 45 spine 45 lesions 45 urinary tract 45 artery 45 synapse 45 spinal fluid 45 degenerative 45 anterior 45 lung 45 bowel 45 nasal passages 45 prostate gland 45 abdominal cavity 45 visual acuity 45 hypothalamus 45 lobes 45 lymphatic system 44 tumor 44 cataract 44 genetic disorder 44 tumors 44 corneas 44 kidney function