Dilation of cervical epidural veins in intracranial hypotension.

FIG 2. Axial T2-weighted turbo spin-echo sequence (3900/120) at C7–T1 level showing increased signal in the paraspinal soft tissues close to the right exiting root. This finding was interpreted as cerebrospinal fluid leakage. FIG 3. Anatomic landmarks for measurement of vertical brain displacement on sagittal T1-weighted MR images (1, cerebellar tonsils; 2, fourth ventricle; 3, infundibular recess; 4/5, angle. A, Symptomatic patient. B, Same patient after a normal follow-up examination. FIG 1. A, MR angiogram obtained with an axial fast low-angle shot 2D sequence (40/ 9.8 [TR/TE]; flip angle, 35Њ). Cervical epi-dural veins are markedly dilated and give very high signal. Carotid and vertebral arteries give dark signal because of inferior saturation. B, Oblique sagittal and coronal reconstructed images obtained with maximum intensity projection. We read with interest the case report of Clarot et al (1) regarding a patient with intracranial hy-potension (IH) after lumbar puncture who had giant cervical epidural veins as the sole MR finding. Having had experience with a similar case, we felt obliged to report on our observation and contribute to the validation of this finding, with the aim of rendering a difficult diagnosis easier. A 34-year-old previously healthy woman presented in May 1996 with headache and neck pain. Spinal MR showed dilation of cervical epidural veins, especially visible from the C2 down to the C4 level anteriorly. On subsequent angiography, no vascular malformation was identified; venous drainage and jugular veins were normal, but epi-dural veins appeared markedly dilated at the upper cervical and spinal-medullary level (Fig 1). Further observation of the spinal MR study made it possible to identify meningeal ectasia at the level of the exiting spinal roots at C7–T1 (Fig 2). At the same level, increased signal was noticed on T2-weighted images in the paraspinal soft tissues, which was interpreted as cerebrospinal fluid. On this basis, spontaneous IH caused by CSF leakage was suspected. Brain MR showed thickened dura, but the patient refused a contrast-enhanced examination. Nevertheless, accurate measurement of brain position in the skull on midsagittal T1-weighted images gave results suggesting a significant rostrocaudal brain displacement (Fig 3). Cer-ebellar tonsils were 2 mm below the Chamberlain line, and the apex of the fourth ventricle was 3 mm below the Twining line. The symptoms and the MR images resolved after conservative therapy (ie, bed rest and hydration). On clinical follow-up 41 months later, the patient denied any relapse of symptoms. In addition to …