Plate 47: Some locations of severe and grave lesions and their sites as diagrammatically indicated.
(1) Circumscribed furuncle of otitis externa - (2) Infection of the cartilage of pinna. (External ear.) - (3) Subperiosteal collection of pus in case of perforated cortex. (Subperiosteal abscess.) - (4) Sinking of post-superior canal wall, during periosteal inflammation, as part of picture of acute mastoiditis - (5) Epidural cerebral abscess - (6) Circumscribed cerebral abscess - (7) Subdural abscess -(8) Cholesteatoma (pseudo) situated in the attic of middle ear - (9) Circumscribed labyrinthitis - (10) Calcareous deposits cause ankylosis of stapes, involving the annular ligament - (11) Fistula opening on roof of tympanic orifice of Eustachian tube leading to disease in petrosal pyramid - (12) When these areas are involved,the labyrinth is the seat of the lesion - (13) By pressure on the auditory nerve, especially its vestibular branches, symptoms of an angle tumor become evident - (14) Perforated ear drum