Mastoidectomy some drilling tips
1. It is better to set the magnification of the microscope between 4 - 6X as this will give a more complete orientation of the drilling area. Higher magnification levels are necessary to appreciate the minute details.
2. It is best to choose the largest possible burr bit for initial drilling as this will cause less damage. Using small burrs is always dangerous.
3. The length of the cutting burr is adjusted according to the depth of the area to be drilled. Shorter the burr length better is the control.
4. Majority of bone drilling should be performed by using cutting burrs. Diamond burrs can be used when drilling is to be performed over facial nerve area, dura, sigmoid sinus or sometimes to obtain hemostasis over bleeding from bone.
5. The hand piece should be held like a pen.
6. Drilling should be performed in a tangential direction as the cutting surface of the burr is present in its sides.
7. The tip of the burr bit should not be used for drilling.
8. Only minimal pressure should be exerted over burr bits during drilling.
9. For fine drilling the head of the patient should always be supported.
10. The direction of rotation of burr should always be away when drilling over important structures. (Reverse).
11. Liberal irrigation should be performed during the whole of the drilling process. This is more important when drilling is performed over facial nerve area / labyrinth.