Hammer and gouge mastoidectomy for acute mastoiditis - Vula ...

the lateral sinus. This region ismeticulously curetted (Figure 15).Figure 13: Vertical trenchSeventh Step: Exploration of PosteroinferiorRegionThe posteroinferior region, which is alsocalled the region of the mastoid vein, isopened with the gouge. The instrument isheld in the same position as describedpreviously but is slanted obliquely frombehind forward and gently forced in withlight taps of the mallet. The procedureprogresses backward toward the posteriorportion of the mastoid from below up.(Figure 14)Figure 14: Opening posteroinferior regionOpening this posteroinferior regionexposes the inner table of the skull whichat this level forms the bony outer shell ofFigure 15: Completed posteroinferiordissectionIf the bony disease is very extensive, thesoft tissues may have to be sectioned by ahorizontal incision perpendicular to theretroauricular incision, forming a “T”, andadditional posterior exposure of themastoid bone done.Eighth Step: Exploration of PosterosuperiorRegion and Lateral Sinus /Sinodural Angle (Figure 16)Trephination is continued from below upand behind forward, burrowingprogressively into the mastoid and to jointhe superficial antral region. The taps onthe gouge are performed cautiously. Theyare made on a tangent to permit the gradualremoval of the cortex over the lateral sinusor even to uncover the venous wall, if thisshould be necessary. The rongeur isdangerous when handled blindly and maypenetrate dura and injure the brain. Thegouge is much more manageable; its actionmore easily controlled. The posterior limitof trephination is determined by the statusof the bone. The process continues untilnormal resistant bone, which does notbleed, is encountered. If haemorrhageoccurs from the mastoid vein, this may be7