MR imaging of CSF-like choroidal fissure and parenchymal cysts of the brain.

Imaging findings of central nervous system neuroepithelial cysts

“…To our knowledge, there are only four reports of thalamic neuroepithelial cysts [1,2,5] with MR imaging findings in three cases [1,2]. There was pathological correlation in 2 cases.…”

“…In one case (case 5), there was no epithelial lining, but the histological material was of limited size, and in the second case [1], a single layer of epithelium was identified. In two cases the thalamic cyst appeared as an incidental finding that did not correlate with the symptoms [migraine headaches [2] and a mild resting tremor of one hand [1]]. In the two other cases, neurological signs or symptoms [pain involving one side of the face [1] and progressive hemiparesis and hemisensory disturbance [5]] correlated with the cyst's location and improved after medical or surgical therapy.…”

“…But they may also be found within the cerebral hemispheres, thalamus, midbrain, pons, cerebellar vermis (parenchymal cysts) [1±6], and in the medial temporal lobe in or near the choroidal fissure (choroidal fissure cysts) [2]. They are called pseudoparenchymal cysts when they communicate with the subarachnoid space through a small opening or through a diverticulum of the subarachnoid space [2]. The etiology of the neuroepithelial cysts is still controversial but developmental anomalies are likely [1,6].…”

“…If located within or near the ventricular system, they may cause obstructive hydrocephalus. But the majority of cysts represent incidental findings that do not correlate with the clinical signs and/or symptoms that prompted the imaging evaluations [2]. Occasionally, spontaneous cyst regression may be observed [6], but enlargement of the cyst is also possible as a result of chronic CSF pulsation or ball valve effect [2].…”

Choroidal Fissure Cysts in Children - Pediatrician Dilemma for Follow-up?

“…The lesion which is seen as round or ovoid in axial section fits well in the choroidal fissure with slight expansion. [4] Sherman et al [5] had studied 34 patients with these types of cysts which fulfil the following criteria in MRI to be included in this group: -no mass effect -no detectable cyst wall -no surrounding edema -no gliosis -no contrast enhancement -homogenous consistency -all sequences resembling CSF intensity. Morioka et al has treated two patients with medication for the partial seizures and no further investigation or management was required.…”