title: Relationship between media-to-lumen ratio of subcutaneous small arteries and wall-to-lumen ratio of retinal arterioles evaluated noninvasively by scanning laser Doppler flowmetry.
abstract: BACKGROUND
  Structural alterations of subcutaneous small resistance arteries, as indicated by an increased media-to-lumen ratio, are frequently present in hypertensive and/or diabetic patients, and may represent the earliest alteration observed. Furthermore, media-to-lumen ratio of small arteries evaluated by micromyography has a strong prognostic significance; however, its extensive evaluation is limited by the invasivity of the assessment, since a biopsy of subcutaneous fat is needed. Noninvasive measurement of wall-to-lumen of retinal arterioles using scanning laser Doppler flowmetry (SLDF) has recently been introduced. However, this new technique has not yet been compared to micromyographic measurement, generally considered the gold standard approach.
  
  
  RESULTS
  We investigated 40 individuals and patients, 24 of them were hypertensive patients and 16 normotensive individuals. All patients underwent a biopsy of subcutaneous fat during an elective surgical intervention. Subcutaneous small resistance arteries were dissected and mounted on a wire myograph, and media-to-lumen ratio was measured. In addition, an evaluation of wall-to-lumen ratio of retinal arterioles by SLDF was performed (Heidelberg Retina Flowmeter, Heidelberg Engineering). A close correlation was observed between media-to-lumen ratio of subcutaneous small arteries and wall-to-lumen ratio of retinal arterioles (r = 0.76, P < 0.001; P < 0.001, r(2) = 0.57).
  
  
  CONCLUSIONS
  A noninvasive and easily repeatable procedure (intraobserver and interobserver variation coefficient <13%) such as an evaluation of the arterioles in the fundus oculi by SLDF may provide similar information regarding microvascular morphology compared with an invasive, accurate and prognostically relevant micromyographic measurement of media-to-lumen ratio of subcutaneous small arteries.
authors.affiliation: Clinica Medica, Department of Medical and Surgical Sciences, University of Brescia, Italy. rizzoni@med.unibs.it
authors.forename: Damiano
authors.initials: D
authors.lastname: Rizzoni
authors.forename: Enzo
authors.initials: E
authors.lastname: Porteri
authors.forename: Sarah
authors.initials: S
authors.lastname: Duse
authors.forename: Carolina
authors.initials: C
authors.lastname: De Ciuceis
authors.forename: Claudia Agabiti
authors.initials: CA
authors.lastname: Rosei
authors.forename: Elisa
authors.initials: E
authors.lastname: La Boria
authors.forename: Francesco
authors.initials: F
authors.lastname: Semeraro
authors.forename: Ciro
authors.initials: C
authors.lastname: Costagliola
authors.forename: Adolfo
authors.initials: A
authors.lastname: Sebastiani
authors.forename: Paola
authors.initials: P
authors.lastname: Danzi
authors.forename: Guido A M
authors.initials: GA
authors.lastname: Tiberio
authors.forename: Stefano M
authors.initials: SM
authors.lastname: Giulini
authors.forename: Franco
authors.initials: F
authors.lastname: Docchio
authors.forename: Giovanna
authors.initials: G
authors.lastname: Sansoni
authors.forename: Annamaria
authors.initials: A
authors.lastname: Sarkar
authors.forename: Enrico Agabiti
authors.initials: EA
authors.lastname: Rosei
mesh_terms: D000328:Adult; D000368:Aged; D001158:Arteries / Q000000981:diagnostic imaging*; D001160:Arterioles / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D017078:Laser-Doppler Flowmetry / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012171:Retinal Vessels / Q000000981:diagnostic imaging*; D014463:Ultrasonography