OBJECT: The authors report on a series of 46 @entity1 harboring @entity5513 ( @entity5513 ) treated using linear accelerator (LINAC) radiosurgery and an analysis of serial magnetic resonance (MR) imaging data, specifically the changes in @entity5 volume. METHODS: Fifty-three consecutive @entity1 underwent LINAC radiosurgery for VS between 1993 and 2002. Seven of these @entity1 were lost to follow up. Three-dimensional (3D) spoiled gradient-echo (SPGR) MR imaging was performed at 3- to 4-month intervals after radiosurgery. @entity5 volume was measured on Gd-enhanced MR images of each slice. The median duration of follow-up MR imaging studies was 56.5 months (range 12-120 months). Follow-up imaging studies were conducted for longer than 1 year in 42 of 53 @entity1 . @entity5 volume changes were categorized into four types: enlargement (eight lesions [19%]), no change (two lesions [4.8%]), transient enlargement followed by shrinkage (19 lesions [45.2%]), and direct shrinkage (13 lesions [31%]). Two cases (4.8%) with twice the initial @entity5 volume required repeated radiosurgery. All cases of transient enlargement had subsequent shrinkage within 2 years after radiosurgery. Nine (21.4%) of 42 @entity1 demonstrated @entity67 on MR images obtained after radiosurgery. Three @entity1 (7.1%) required placement of a ventriculoperitoneal shunt because of symptomatic @entity1276 , and another four cases (9.5%) spontaneously resolved. CONCLUSIONS: Volume measurement on 3D-SPGR MR imaging was a suitable method to assess @entity5 changes. Volume changes beyond twofold or continuous enlargement for longer than 2 years after radiosurgery are key criteria in rating the effects of radiation. Some cases of @entity1276 after radiosurgery resolved spontaneously and their rates of occurrence were similar to the typical incidence of @entity1276 associated with VS.

Linear accelerator radiosurgery for XXXX : measuring @entity5 volume changes on serial three-dimensional spoiled gradient-echo magnetic resonance images.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity5513 :: ('MESH:D009464', 'Disease') :: ['VSs', 'vestibular schwannomas'] @entity1276 :: ('MESH:D006849', 'Disease') :: ['hydrocephalus'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'Tumor'] @entity67 :: ('MESH:D018754', 'Disease') :: ['ventricular enlargement']
@entity5513 :: (MESH:D009464,Disease) :: ['vestibular schwannoma']
