title: Evidence for aggregation in oxalate stone formation: atomic force and low voltage scanning electron microscopy.
abstract: OBJECTIVE
  The aim of this investigation was to differentiate between aggregation and crystal growth by studying the structure of oxalate stones at high spatial resolution using recently developed microscopy techniques.
  
  
  METHODS
  Sections from 6 complete human oxalate stones and 4 stone fragments were prepared by ultramicrotomy and examined by both low voltage scanning electron microscopy and atomic force microscopy.
  
  
  RESULTS
  The scanning electron microscopy showed lamellar structures up to 10 microns. in size, consistent with previous results, and provided evidence that these structures were composed of smaller particles. The atomic force microscopy clearly showed arrays of the small particles, whose size varied between 500A and 2800A.
  
  
  CONCLUSIONS
  Our images suggest that an ordered aggregation of small crystallites is responsible for oxalate stone formation.
authors.affiliation: Center for Solid State Science, Arizona State University, Tempe 85287-1704, USA.
authors.forename: H H
authors.initials: HH
authors.lastname: Dorian
authors.forename: P
authors.initials: P
authors.lastname: Rez
authors.forename: G W
authors.initials: GW
authors.lastname: Drach
mesh_terms: D006801:Humans; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D010070:Oxalates / Q000032:analysis*; D019815:Oxalic Acid; D014545:Urinary Calculi / Q000737:chemistry*
chemical_list: D010070:Oxalates; D019815:Oxalic Acid