TYMPANIC MEMBRANE 

 # It is a pearly grey in colour # Oval 9-10 mm in diameter # surface area 90 sq mm # Outer part is more mobile than central part . # The effective surface area is 55 sq mm . # It is lying at an angle of 55 degree with horizontal  # Posterosuperior part is more lateral than anterolateral part . # Shows mobility on Seigelisation ( Putting air pressure on ear drum ) 

# Landmarks : 1 ) Handle of Malleus 2 ) Lateral process of malleus 3) Cone of light produced by refecltion of light from handle of malleus . Seen in  right ear at 5 o' clock position and Left ear at 7 o' clock position . 5 ) Umbo 

                                               IT has 2 part 1) Pars Tensa : which again has 3 layers a) SKIN                                                   b) Fibrous layer c) Mucosa 

                                                                      2) Pars Flacida : It has 2 layers a) Skin b) Mucosa 

Uses of Siegel Speculum : 1) To check the mobility of TM 2) To suck all secretions from middle ear 3) Fistula sign can be evaluated = If there is inner ear fistula , on pressure by siegel speculum there is vertigo . 4) To spray antibiotics in EAC 

  Nerve supply of tympanic membrane: Lateral Surface : Same 

 as EAC . Anteriorly : Auriculotemporal nerve 

                Posteriorly : Auricular branch of vagus . 

   Medial surface : Toward the middle ear it is same as sensory 

 supply of ME by tympanic branch of Glossopharyngeal nerve a/k/s Jacobson's nerve .*** This nerve is the cause of referred otalgia in many conditions like Tonsillitis , after Tonsillectomy , Stylalgia or Ca of base of the tongue . 

  RETRACTED TYMPANIC MEMBRANE :: 

  # It is due to negative middle ear pressure caused by ET blockage. 

  # Dull in appearance 

 # Handle of MAlleus medialised 

  # Lateral process of malleus become more prominent .

  # Cone of light is absent . 

  # On siegelisation mobility absent or reduced . 

    RETRACTION POCKET: : There is much more retraction . It is more commonl;y seen in Pars flaccida . These are lined by skin and filled with keratin .

Siegel's speculum