Again, the park-bench position is used. The usual preparations are made, the approach being made through an extended incision to allow access to the upper lateral aspect of the cervical spine. Exposure of the posterior fossa dura is like a retro-mastoid craniotomy for a CPA lesion. However, the sub-occipital muscles are reflected like the leaves of a book to define the transverse process and lamina of C1 and the upper aspect of C2. The vertebral artery courses over the arch of C1 before it enters the posterior fossa via the foramen magnum. Depending upon the extent of the exposure, the artery can be transposed to widen the amount of C1 arch that can be removed and, following that, the amount of the foramen magnum that is removed. Clearly, the further forward this is taken, the more of the condylar joint is removed and thus the greater the requirement for postoperative stabilization. However, failure to remove sufficient amounts of the joint will restrict visibility and access to the anterior part of the foramen magnum and the lower clivus. If exposure is limited, more bone can always be removed.
Once the bone work is completed, dural opening will allow exposure of the area. Within the dura at the foramen magnum lies a dural sinus that has to be divided. The dura is remarkably thick in this area, and the use of stitches to retract the dura may assist the opening process. Be prepared to use artery clips to stop the bleeding whilst completing the dural opening -getting haemostasis is then easier.
Closure of the dura will not be possible without insertion of a dural patch. Again, using a lumbar drain may reduce the incidence of CSF leakage.
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The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.