Diffuse pachymeningeal Enhancement on Brain MRI

Purpose: We evaluated the MRI finding of pachymeningeal enhancement in patients with intracranial hypotension and head trauma with particular attention to differential findings and change in follow-up study, and in order to support the knowledge about the pathophysiology of d ural enhancement. Materials and Methods : The findings of enhanced brain MRI offifteen patients who showed diffuse pachymeningeal enhancement were retrospectively examined. Seven of fifteen patients were finally diagnosed as spontaneous intracranial hypotension (SIH) . Eight of fifteen patients had a recent history of head trauma. We analyzed the shape, thickness , continuity and extent of dural enhancement , and the others concerned with positive MR findings. We also analyzed findings suggested displacement of brain parenchymadisplacement of the iter and cerebellar tonsil, and f1attening of the anterior aspect of the pons. Four of seven patients with SIH and four of eight patients with head trauma, underwent fl이low-up MRI. In the follow-up study, the presence of resolving pachymeningeal enhancement and symptom improvement was investigated. Results : In all cases of SIH, the dura showed diffuse, even 3 (1 mm thick, global and contiguous enhancement along both cerebral convexities, both tentoria, and the falx. Displacement of the iter was noted in six cases and f1attening of the anterior aspect of the pons in five. Displacement of the cerebellar tonsil was noted in one case. Five of seven cases showed small amount of subdural f1uid collection. In all èases ofhead trauma, the dura was enhanced diffusely and asymmetrically, and showed no contiguity. Its distribution was consistent with the locations of traumatic lesions. Displacement of the iter was noted in one case. In four cases of SIH, clinical symptoms had improved, and three showed complete resolution of dural enhancement, in one patient continuously showed partial dural enhancement. Four cases ofhead trauma showed complete resolution of dural enhancement. Conclusion : Reversible diffuse pachymeningeal enhancement and additional findings in brain MRI of SIH and head trauma are valuable for differenciation from other irreversible pathological conditions related to pachymeningeal enhancement and to support the knowledge about pathophysiology of dural enhancement.