As a person ages, there skin gets weak. The skin in the neck can get saggy and loose which can caused the neck lines to appear with age. Horizontal lines are due to collagen deficiency. Vertical lines are due to keeping the neck in the same position for a long time.
Neck lines are caused due to over exposure to the sun, ageing. Sun exposure damages the collagen and weakens the skin which can causes fine lines in the neck. Smoking and caffeine can be additional risks for neck lines.
Neck line treatment is a procedure that can be used to remove the neck lines which can be done by Laser, surgery or Botox. Over exposure to sun has to be avoided immediately after the treatment.