Otoscopic image (panel A) and schematic diagram (panel B) of a left tympanic membrane. A line drawn along the manubrium of the malleus divides the tympanic membrane into anterior and posterior halves (dashed line). A line drawn through the umbo (perpendicular to the first line) divides the tympanic membrane into superior and inferior halves (solid line).
I: incus, long process; L: lateral process of the malleus; LR: light reflex; M: manubrium of the malleus; PF: pars flaccida; PT: pars tensa; U: umbo.