Page 99 - Edited - Webster HEAD AND NECK - part 2-Merge PDF

HN 293 THE OUTER EAR (2) HN 293

(A) MISALIGNMENT OF LATERAL & MEDIAL (B) PULLING THE
ENDS OF THE EXTERNAL MEATUS IS PINNA UPWARDS &
NORMAL. BACKWARDS

COMPENSATES FOR
MOST (BUT NOT QUITE
ALL-NOTE ANTERIOR
MARGIN) OF THIS
MISALIGNMENT.
POSITION OF
TYMPANIC
MEMBRANE

EXTERNAL
OPENING
OF MEATUS

The external auditory meatus is curved, so that its external opening lies not only lateral to but anterior and
inferior to the circumference of the ear drum. The flexibility of the cartilaginous meatus means that if the pinna
is pulled upwards and backwards, the two are roughly aligned, as shown above at (B). This manoeuvre is
required for effective inspection of the tympanic membrane with an auroscope, as at (C).

C. VIEN OF TYMPANIC
MEMBRANE THROUGH FLACCID PART OF
AN AUROSCOPE TYMPANIC MEMBRANE
(corresponds with lower limit
of epitympanic receres -
SHEET 194).

ANTERIOR POSTERIOR WALL OF
WALL OF MEATUS
EXTERNAL
MEATUS (see B,
above) TENSE PART OF
TYMPANIC MEMBRANE

NOTICE the HANDLE &
UMBO of THE MALLEUS
(the first of the ossicles)
attached to the INNER The CONE of LIGHT is HEAD
SURFACE of the ear drum reflected from the auroscope
which is thin enough to reveal light & is the result of the FLACCID OF
them. The NORMAL DRUM conical shape of the normal MALLEUS
is a PEARLY WHITE drum, exaggerated in HANDLE

COLOUR. diagram D. → UMBO

MEATUS MIDDLE EAR
In D., notice that the HEAD of the MALLEUS pro TENSE
funded above the highest level of the tympanic
membrane.
kewteachear/nodes