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Related to arachnoidal: Arachnoid villi, arachnoid cyst


Relating to the arachnoid membrane, or arachnoidea.


/arach·noi·dal/ (ar″ak-noi´d'l) pertaining to the arachnoid.

Patient discussion about arachnoidal

Q. What is the treatment for an arachnoid cyst? My 15 year old son has just been diagnosed with an arachnoid cyst. What is the treatment? Is an operation necessary?

A. An operation is not always necessary, it depends on the size and location of the cyst. I suggest you take your son to a neurologist or a neurosurgeon for further consult.

Q. info on arachnoid cyst in the right posterior fossa

A. Basically it's like a small sac filled with fluid. The problem is that the skull is a rigid closed space, which means that if there's something other than the brain, it'll occupy space, usually on expense of the brains' space. These kinds of problems are often referred to as "space occupying lesion".

It's usually congenital (i.e. develops during pregnancy), and even when it cause symptoms they develop slowly.

YOu can read more here (

Q. Is there any problem, if an arachnoid cyst ,2cmx1.5cm size, rostral to cerebellar region left untreated? symptoms: repeated headaches, twitching of muscles, tiredness

A. An arachnoid cyst that leads to symptoms usually needs treatment. Mild symptoms as you suggested are ok to left untreated however gradual onset of new symptoms may arise such as seizures, paralysis and other complications, therefore once symptoms occur one should consider treatment.

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References in periodicals archive ?
Blood vessel wall was not changed in comparison with D2; however, border arachnoidal cells were highly positive (panel (d)).
Chronic subdural hemorrhage into a giant arachnoidal cyst (Galassi classification type IH).
Pacchionian granulations are hypertrophic arachnoidal villi, which can erode through cranial bone, causing lytic lesions on skull roentgenograms or computed tomography (CT) scans.
Jennie was born with an arachnoidal cyst on the left side of her brain.
These included patient 1 with a multiloculated cyst, possibly of arachnoidal origin (Figure 1, A), in which innumerable S100-positive nerve rootlets were entrapped in cyst wall.
However, arachnoidal cells have been identified outside the neural axis, which may give rise to intratympanic or temporal bone meningiomas.
Indeed, in these cases, bone invasion may also develop by contiguity from a spinal arachnoidal graft.
9] Arachnoidal cysts, which are not true neoplasms, can also involve the petrous apex and cause symptoms that mimic neoplasms in this region.
The most common congenital lesions that occur in the cerebellopontine angle cistern and internal acoustic canal are epidermoidomas, arachnoidal cysts, dermoids, and lipomas.