Neurosurgery

and this may not be the level of the cutaneous stigma (an important point preoperatively), CT scanning with intrathecal contrast may demonstrate a bony spur. Nevertheless, with modern MRI, CT myelography is generally no longer necessary.

Neurological deterioration in split cord malformations is generally considered to be a result of tethering, although associated lesions such as hydromyelia may contribute. The aim of surgery, therefore, is to remove the bony or fibrocartilaginous spur and to excise the dural sleeve surrounding it. In cases with separate dural tubes, each containing a hemicord (type I split cord malformations), the tethering spur is found at the caudal end of the divided dural tube (Fig. 27.4a). The cutaneous mark may not necessarily lie over the bony abnormality but there is usually an abnormal lamina present. Surgery involves identifying the lowermost normal lamina and then carrying out a laminec-tomy of the abnormal lamina below, it usually being necessary to include the lowermost normal lamina. The spur is then isolated and removed down between the two dural tubes. The stalk and surrounding epidural veins can bleed briskly and this should be anticipated. Once the stalk has been removed, the dura is opened around the cleft, revealing the hemicords, which usually unite just below the location of the spur. Pang emphasizes the importance of dividing any fibrous bands and median nerve roots, which are non-functioning, coursing dorsally to tether the hemicords. These bands may continue to the subcutaneous tissues, forming the entity known as a meningocele manqué [23]. The dural sleeve around the spur should be excised to ensure that the union of the hemicords is free to "ride up". It is not necessary to close the ventral dura but the

Fig. 27.4. a Type I split cord malformation at operation. The two dural tubes containing the hemicords unite just below the dividing spur, with associated nerve roots visible. bType II split cord malformation. Two hemicords visible within a single dural tube on CT myelography. The lateral nerve roots are well seen.

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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