(Latin) Having great strength
n. (pl. cisternae) 1. one of the enlarged spaces beneath the *arachnoid that act as reservoirs for cerebrospinal fluid. The largest (cisterna magna) lies beneath the cerebellum and behind the medulla oblongata. 2. a dilatation at the lower end of the thoracic duct, into which the great lymph ducts of the lower limbs drain.... cisterna
an operation in which a *shunt is created between the lateral *ventricle of the brain and the *cisterna magna to bypass a block of the cerebral *aqueduct and thus relieve *hydrocephalus. Originally this was achieved by means of an external indwelling catheter, but later techniques use an internal catheter, which reduces the risk of septic complications. [A. Torkildsen (20th century), Norwegian neurosurgeon]... torkildsen procedure