Neurosurgery

caused by Gram-negative bacilli. In infants and children, most cases are caused by the organisms responsible for meningitis in this age group, namely H. influenza, E. coli and S. pneumoniae.

Laboratory findings are non-specific and but include peripheral leukocytosis and/or positive blood cultures. Lumbar puncture is contraindi-cated, due to the risk of herniation, and adds little information, although there are considerable CSF data in the literature.

CT and MRI have become the cornerstones of diagnosis. The CT appearance of SDE is that of a hypodense, crescentic or lenticular, extra-axial fluid collection. If contrast is administered, a densely enhancing inner membrane, which displaces the gray-white junction, is often noted. There are frequently adjacent parenchymal edema and midline shift that may be dramatically out of proportion to the size of the collection - a feature that should raise the index of suspicion for an SDE. Early on, CT may miss a small collection, particularly a small parafalcine or interhemispheric collection or a posterior fossa empyema. In difficult cases, MRI is probably more sensitive in detecting small collections in difficult areas. An SDE typically appears hypointense on T1WI and hyperintense on T2WI. Administration of gadolinium may delineate a membrane similar to CT. The multi-planar imaging capabilities of MRI provide more precise anatomical localization than does CT without any bone-averaging artifact. It has been suggested that MRI is able to differentiate between SDE and a non-infected sub-dural effusion. Most often, MRI is capable of differentiating an EDA from an SDE and is more sensitive in detecting small, early empyemas [21].

Management of SDE involves emergent drainage of the purulent collection, along with antibiotics. There has been extensive debate regarding surgical management, with some authors advocating drainage through multiple burr holes, while others promote, de novo, a wide craniotomy [22]. Advocates of burr-hole drainage maintain that craniotomy has a higher risk and may necessitate performing a delayed cranioplasty. Furthermore, those favoring burr-hole drainage contend that extensive irrigation through multiple burr holes is sufficient, unless the collection is parafalcine. Advocates of cran-iotomy point out that incomplete drainage using burr holes often necessitates performing a craniotomy at a later time. Regardless of the type of surgery elected, timing of surgery is critical, with optimal results obtained when surgery is performed within 3-5 days of symptom onset. Following surgical evacuation, antibiotics should be administered for 4-6 weeks, based on culture and sensitivity testing.

Previously, the mortality from SDE has been as high as 40-50%, although more recent series report rates of between 10 and 20% [22]. Unfortunately, survivors often are left with significant neurological dysfunction and epilepsy may occur, either acutely or in a delayed fashion. The prognosis for patients with SDE is most closely associated with the degree of neurological dysfunction at the time of diagnosis, especially the level of consciousness. Mortality appears to be somewhat better in patients treated with craniotomy, although it is unclear whether this reflects an advantage of craniotomy or the better medical condition of these patients [22].

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

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.

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