Comparison of conventional myelography with computed tomograrhic myelography

ABSTRACT

This study was conducted over a period of six months in the department of radiology of Mayo Hospital, Lahore with the sole objective of comparing the conventional myelography with the newer, relatively, the computed tomographic myelography. We evaluated the results and compiled the data for the same reason. 30 patients who were symptomatic were collected from the neurology and the neurosurgery department's. The symptoms of the patients varied from having complete quadriplegia to simple tingling sensations. The conventional myelography was conducted on X-ray Machine under fluoroscopic control. After the procedure the patients were taken to the CT machine for the CT scan and the area under investigation was scanned. While compiling the data it was found that out of 30 patients 9 were normal as far as the myelography was concerned. 15 had extradural compression on the cord, 5 had intramedullary lesions while 1 patient had intradural but extra medullary lesion. And there were 3 cases in which the conventional myelography showed false results. In 2 the result was interpreted as intramedullary on conventional myelography but the CT showed it to be clearly extradural. The results were later compared with the patient out come. All intramedullary lesions went for surgical management and results were 100 percent correct. So we concluded that the conventional myelography was 94 percent specific in localizing the lesion as compared with the 100 percent of the CT scan. But due to the cost effectiveness and the availability of modality and the relatively low radiation dose the conventional myelography has to be the modality of initial choice. And CT should only be done at the areas of interest to avoid any unnecessary radiation