Imaging Features of Unsuccessful CT Myelography and Gadolinium-enhanced MR Myelography in Spontaneous Intracranial Hypotension / 中国医学影像学杂志

ABSTRACT

PurposeCT myelography (CTM) and gadolinium-enhanced MR myelography (Gd-MRM) are essential methods used for localizing spinal cerebrospinal fluid leaks in patients with spontaneous intracranial hypotension (SIH) and are significant for diagnosis and guided epidural blood patches. This paper analyzes the rate and imaging features of unsuccessful myelography due to misinjection of contrast into epidural space to guide prompt and correct clinical judgment of unsuccessful myelography.Materials and Methods Myelography from 121 patients with SIH was retrospectively reviewed and the image features of the unsuccessful myelography were analyzed.Results A total of 128 myelography examinations were done. Contrast media was accidently injected into the epidural space in 33 examinations. The failure rate was 25.8%. In all 33 failed exams, bilateral spinal nerve roots on both sides of the dural sac passing through contrast media was observed without visualization of anterior and posterior nerve roots. Cauda equina was not seen within contrast media in 29 cases (87.9%); non-diffusion of contrast media into cisterns and ventricles in 26 cases (78.8%). Contrast was not continuous in spinal canal in 16 cases (48.5%), heterogeneous in 10 cases (30.3%). In 4 cases (12.1%) the inner contour of contrast was not smooth.Conclusion The unsuccessful rate of myelography is relatively high in SIH patients. A prompt and correct decision could be made based on the knowledge of contrast misinjection imaging features.