The best operative intervention for children with arachnoid cysts remains the 
subject of controversy. Recent reports stress that craniotomy for cyst 
fenestration is associated with a low incidence of morbidity and mortality and 
may leave the child shunt-independent. Among a total of 66 intracranial 
arachnoid cysts operated on in the authors' department from 1985 to 1997, 44 
cases (67%) were located in the middle cranial fossa. A higher incidence in the 
first decade of life (53 cases) and a marked male predominance (45 cases) were 
recognized. Headache, cranial deformities, symptoms of raised intracranial 
pressure, and seizures constituted the most frequent features of the clinical 
presentation. To determine which treatment provides the greatest benefit with 
the lowest incidence of complications, the records of the 44 patients with 
arachnoid cysts in the middle cranial fossa were reviewed. The mean age of these 
patients was 4.6 years (range 0-16 years). Different types of initial surgical 
procedures were performed. In 33 patients with middle cranial fossa arachnoid 
cysts (MCFAC) the initial surgery took the form of craniotomy with excision of 
the cyst walls and fenestration into the basal cisterns. Shunting procedures 
were performed in 9 patients: cysto-peritoneal shunts (CPS) were placed in 4 
patients and ventriculo-peritoneal shunts (VPS), in 3 patients, and cyst 
excision was performed in addition to CPS in 2 patients. Excision of the cyst 
membrane alone without fenestration was performed in 2 patients. The initial 
treatment was successful in terms of reduced symptoms and decreased cyst size, 
with no additional treatment needed for the cyst, in 79% (26/33) of patients who 
had undergone excision of the cyst walls and fenestration into the basal 
cisterns, compared with 66% (6/9) of patients who had undergone shunting 
procedures. Cyst membrane excision was not successful in any of the patients who 
underwent this procedure alone. No significant difference in morbidity was noted 
between these different treatment options. On follow-up CT scan and MRI, cysts 
of types I and II (Galassi classification) exhibited a steady tendency to 
reduction or obliteration. These results confirm that radical excision of the 
outer and inner membranes of the cyst wall with fenestration into the basal 
cistern is a safe and effective shunt-independent procedure for MCFAC, 
especially for those of types I and II.