title: Intracranial cryosurgery in a canine model: a pilot study.
abstract: Although virtually abandoned decades ago following the introduction of levodopa for the treatment of movement disorders, intracranial cryosurgery potentially offers a simple and accurate means of destroying deep-seated lesions when coupled with computed tomographic-stereotaxic placement techniques. We performed a pilot investigation of the size and histology of brain cryolesions in six dogs, using a 3-mm probe maintained at -160 degrees C for 6 minutes while simiultaneously monitoring the process by real-time ultrasound. Lesion diameter was 1.4 +/- 0.1 cm at less than or equal to 2 days but enlarged to 2.25 +/- 0.21 cm at 1 week, primarily at the expense of white matter. Ultrasound appearance of the lesion was characterized by a hyperechoic ice ball, the size of which consistently underestimated true size (determined by histology). By microscopy, the lesion was a hemorrhagic infarction that incited little surrounding edema and exhibited a sharp transitional zone. These data indicate that the cryosurgical probe can lesion significant volumes of brain in a reproducible and discrete fashion with minimal reaction to the surrounding tissue. Further work is required to clarify the observed "growth" of lesion size between days 2 and 7.
authors.affiliation: Department of Neurosurgery, Allegheny General Hospital, Pittsburgh, Pennsylvania 15212.
authors.forename: M R
authors.initials: MR
authors.lastname: Quigley
authors.forename: D V
authors.initials: DV
authors.lastname: Loesch
authors.forename: T
authors.initials: T
authors.lastname: Shih
authors.forename: M
authors.initials: M
authors.lastname: Marquardt
authors.forename: A
authors.initials: A
authors.lastname: Lupetin
authors.forename: J C
authors.initials: JC
authors.lastname: Maroon
mesh_terms: D000818:Animals; D001927:Brain Diseases / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy*; D003452:Cryosurgery; D004195:Disease Models, Animal; D004285:Dogs; D008297:Male; D014463:Ultrasonography