Do arachnoid cysts grow?

Abstract

The volumes of intracranial arachnoid cysts were measured in 136 CT scans of 86 patients. Absolute and relative cyst size was calculated. Left hemisphere and middle cranial fossa location prevailed. A slight negative correlation of relative cyst size with age (r = -0.21, NS) disappeared when analysis was restricted to the adult age group (greater than or equal to 20 years). After the sample was divided into two groups according to relative cyst size (cysts less than mean volume vs cysts greater than mean volume), small AC showed no correlation with age, while large AC correlated positively with age (r = 0.79, P less than 0.05). A subgroup of large AC appears to expand with time, while the majority of small AC remain unchanged.

Cerebellopontine Angle Arachnoid Cyst Harbouring Ectopic Neuroglia

“…The arachnoid cysts become symptomatic during childhood in about 70–90% [3,4,5,6,7,8]. Besides the theory of a congenital origin of these pathologic findings, reports also support the hypothesis of acquiring these arachnoid cysts due to mechanisms such as infection, trauma, pressure or CSF flow changes [9,10,11].…”

Congenital Middle Fossa Arachnoid Cysts May Cause Global Brain Ischaemia: A Study with ⁹⁹Tc-Hexamethylpropyleneamineoxime Single Photon Emission Computerised Tomography Scans

“…The relevance of these observations is whether one would expect the temporal lobe to expand after successful treatment or not. Regardless of origin, several studies have shown that a large proportion of middle fossa arachnoid cysts enlarge with time [5, 6, 7, 8]. …”

Arachnoid Cyst Rupture with Concurrent Subdural Hygroma

“…The majority of these cysts occur in the middle cranial fossa. Large middle fossa arachnoid cysts are more likely to be symptomatic, and appear to have the highest risk of undergoing significant expansion [2]. There appears to be a male predominance for these lesions [4, 8, 11].…”

“…These are benign lesions that usually remain fairly stable in size. Despite this, between 60 and 80% become symptomatic [2]. Occasionally, intracystic hemorrhage occurs with or without preceding trauma [3].…”